initial commit

5 files changed, 2549 insertions, 0 deletions

diff --git a/lib/python2.7/site-packages/pip/req/__init__.py b/lib/python2.7/site-packages/pip/req/__init__.py
new file mode 100644
index 0000000..00185a4
--- /dev/null
+++ b/lib/python2.7/site-packages/pip/req/__init__.py
@@ -0,0 +1,10 @@
+from __future__ import absolute_import
+
+from .req_install import InstallRequirement
+from .req_set import RequirementSet, Requirements
+from .req_file import parse_requirements
+
+__all__ = [
+    "RequirementSet", "Requirements", "InstallRequirement",
+    "parse_requirements",
+]
diff --git a/lib/python2.7/site-packages/pip/req/req_file.py b/lib/python2.7/site-packages/pip/req/req_file.py
new file mode 100644
index 0000000..821df22
--- /dev/null
+++ b/lib/python2.7/site-packages/pip/req/req_file.py
@@ -0,0 +1,342 @@
+"""
+Requirements file parsing
+"""
+
+from __future__ import absolute_import
+
+import os
+import re
+import shlex
+import sys
+import optparse
+import warnings
+
+from pip._vendor.six.moves.urllib import parse as urllib_parse
+from pip._vendor.six.moves import filterfalse
+
+import pip
+from pip.download import get_file_content
+from pip.req.req_install import InstallRequirement
+from pip.exceptions import (RequirementsFileParseError)
+from pip.utils.deprecation import RemovedInPip10Warning
+from pip import cmdoptions
+
+__all__ = ['parse_requirements']
+
+SCHEME_RE = re.compile(r'^(http|https|file):', re.I)
+COMMENT_RE = re.compile(r'(^|\s)+#.*$')
+
+SUPPORTED_OPTIONS = [
+    cmdoptions.constraints,
+    cmdoptions.editable,
+    cmdoptions.requirements,
+    cmdoptions.no_index,
+    cmdoptions.index_url,
+    cmdoptions.find_links,
+    cmdoptions.extra_index_url,
+    cmdoptions.allow_external,
+    cmdoptions.allow_all_external,
+    cmdoptions.no_allow_external,
+    cmdoptions.allow_unsafe,
+    cmdoptions.no_allow_unsafe,
+    cmdoptions.use_wheel,
+    cmdoptions.no_use_wheel,
+    cmdoptions.always_unzip,
+    cmdoptions.no_binary,
+    cmdoptions.only_binary,
+    cmdoptions.pre,
+    cmdoptions.process_dependency_links,
+    cmdoptions.trusted_host,
+    cmdoptions.require_hashes,
+]
+
+# options to be passed to requirements
+SUPPORTED_OPTIONS_REQ = [
+    cmdoptions.install_options,
+    cmdoptions.global_options,
+    cmdoptions.hash,
+]
+
+# the 'dest' string values
+SUPPORTED_OPTIONS_REQ_DEST = [o().dest for o in SUPPORTED_OPTIONS_REQ]
+
+
+def parse_requirements(filename, finder=None, comes_from=None, options=None,
+                       session=None, constraint=False, wheel_cache=None):
+    """Parse a requirements file and yield InstallRequirement instances.
+
+    :param filename:    Path or url of requirements file.
+    :param finder:      Instance of pip.index.PackageFinder.
+    :param comes_from:  Origin description of requirements.
+    :param options:     cli options.
+    :param session:     Instance of pip.download.PipSession.
+    :param constraint:  If true, parsing a constraint file rather than
+        requirements file.
+    :param wheel_cache: Instance of pip.wheel.WheelCache
+    """
+    if session is None:
+        raise TypeError(
+            "parse_requirements() missing 1 required keyword argument: "
+            "'session'"
+        )
+
+    _, content = get_file_content(
+        filename, comes_from=comes_from, session=session
+    )
+
+    lines_enum = preprocess(content, options)
+
+    for line_number, line in lines_enum:
+        req_iter = process_line(line, filename, line_number, finder,
+                                comes_from, options, session, wheel_cache,
+                                constraint=constraint)
+        for req in req_iter:
+            yield req
+
+
+def preprocess(content, options):
+    """Split, filter, and join lines, and return a line iterator
+
+    :param content: the content of the requirements file
+    :param options: cli options
+    """
+    lines_enum = enumerate(content.splitlines(), start=1)
+    lines_enum = join_lines(lines_enum)
+    lines_enum = ignore_comments(lines_enum)
+    lines_enum = skip_regex(lines_enum, options)
+    return lines_enum
+
+
+def process_line(line, filename, line_number, finder=None, comes_from=None,
+                 options=None, session=None, wheel_cache=None,
+                 constraint=False):
+    """Process a single requirements line; This can result in creating/yielding
+    requirements, or updating the finder.
+
+    For lines that contain requirements, the only options that have an effect
+    are from SUPPORTED_OPTIONS_REQ, and they are scoped to the
+    requirement. Other options from SUPPORTED_OPTIONS may be present, but are
+    ignored.
+
+    For lines that do not contain requirements, the only options that have an
+    effect are from SUPPORTED_OPTIONS. Options from SUPPORTED_OPTIONS_REQ may
+    be present, but are ignored. These lines may contain multiple options
+    (although our docs imply only one is supported), and all our parsed and
+    affect the finder.
+
+    :param constraint: If True, parsing a constraints file.
+    :param options: OptionParser options that we may update
+    """
+    parser = build_parser()
+    defaults = parser.get_default_values()
+    defaults.index_url = None
+    if finder:
+        # `finder.format_control` will be updated during parsing
+        defaults.format_control = finder.format_control
+    args_str, options_str = break_args_options(line)
+    if sys.version_info < (2, 7, 3):
+        # Prior to 2.7.3, shlex cannot deal with unicode entries
+        options_str = options_str.encode('utf8')
+    opts, _ = parser.parse_args(shlex.split(options_str), defaults)
+
+    # preserve for the nested code path
+    line_comes_from = '%s %s (line %s)' % (
+        '-c' if constraint else '-r', filename, line_number)
+
+    # yield a line requirement
+    if args_str:
+        isolated = options.isolated_mode if options else False
+        if options:
+            cmdoptions.check_install_build_global(options, opts)
+        # get the options that apply to requirements
+        req_options = {}
+        for dest in SUPPORTED_OPTIONS_REQ_DEST:
+            if dest in opts.__dict__ and opts.__dict__[dest]:
+                req_options[dest] = opts.__dict__[dest]
+        yield InstallRequirement.from_line(
+            args_str, line_comes_from, constraint=constraint,
+            isolated=isolated, options=req_options, wheel_cache=wheel_cache
+        )
+
+    # yield an editable requirement
+    elif opts.editables:
+        isolated = options.isolated_mode if options else False
+        default_vcs = options.default_vcs if options else None
+        yield InstallRequirement.from_editable(
+            opts.editables[0], comes_from=line_comes_from,
+            constraint=constraint, default_vcs=default_vcs, isolated=isolated,
+            wheel_cache=wheel_cache
+        )
+
+    # parse a nested requirements file
+    elif opts.requirements or opts.constraints:
+        if opts.requirements:
+            req_path = opts.requirements[0]
+            nested_constraint = False
+        else:
+            req_path = opts.constraints[0]
+            nested_constraint = True
+        # original file is over http
+        if SCHEME_RE.search(filename):
+            # do a url join so relative paths work
+            req_path = urllib_parse.urljoin(filename, req_path)
+        # original file and nested file are paths
+        elif not SCHEME_RE.search(req_path):
+            # do a join so relative paths work
+            req_path = os.path.join(os.path.dirname(filename), req_path)
+        # TODO: Why not use `comes_from='-r {} (line {})'` here as well?
+        parser = parse_requirements(
+            req_path, finder, comes_from, options, session,
+            constraint=nested_constraint, wheel_cache=wheel_cache
+        )
+        for req in parser:
+            yield req
+
+    # percolate hash-checking option upward
+    elif opts.require_hashes:
+        options.require_hashes = opts.require_hashes
+
+    # set finder options
+    elif finder:
+        if opts.allow_external:
+            warnings.warn(
+                "--allow-external has been deprecated and will be removed in "
+                "the future. Due to changes in the repository protocol, it no "
+                "longer has any effect.",
+                RemovedInPip10Warning,
+            )
+
+        if opts.allow_all_external:
+            warnings.warn(
+                "--allow-all-external has been deprecated and will be removed "
+                "in the future. Due to changes in the repository protocol, it "
+                "no longer has any effect.",
+                RemovedInPip10Warning,
+            )
+
+        if opts.allow_unverified:
+            warnings.warn(
+                "--allow-unverified has been deprecated and will be removed "
+                "in the future. Due to changes in the repository protocol, it "
+                "no longer has any effect.",
+                RemovedInPip10Warning,
+            )
+
+        if opts.index_url:
+            finder.index_urls = [opts.index_url]
+        if opts.use_wheel is False:
+            finder.use_wheel = False
+            pip.index.fmt_ctl_no_use_wheel(finder.format_control)
+        if opts.no_index is True:
+            finder.index_urls = []
+        if opts.extra_index_urls:
+            finder.index_urls.extend(opts.extra_index_urls)
+        if opts.find_links:
+            # FIXME: it would be nice to keep track of the source
+            # of the find_links: support a find-links local path
+            # relative to a requirements file.
+            value = opts.find_links[0]
+            req_dir = os.path.dirname(os.path.abspath(filename))
+            relative_to_reqs_file = os.path.join(req_dir, value)
+            if os.path.exists(relative_to_reqs_file):
+                value = relative_to_reqs_file
+            finder.find_links.append(value)
+        if opts.pre:
+            finder.allow_all_prereleases = True
+        if opts.process_dependency_links:
+            finder.process_dependency_links = True
+        if opts.trusted_hosts:
+            finder.secure_origins.extend(
+                ("*", host, "*") for host in opts.trusted_hosts)
+
+
+def break_args_options(line):
+    """Break up the line into an args and options string.  We only want to shlex
+    (and then optparse) the options, not the args.  args can contain markers
+    which are corrupted by shlex.
+    """
+    tokens = line.split(' ')
+    args = []
+    options = tokens[:]
+    for token in tokens:
+        if token.startswith('-') or token.startswith('--'):
+            break
+        else:
+            args.append(token)
+            options.pop(0)
+    return ' '.join(args), ' '.join(options)
+
+
+def build_parser():
+    """
+    Return a parser for parsing requirement lines
+    """
+    parser = optparse.OptionParser(add_help_option=False)
+
+    option_factories = SUPPORTED_OPTIONS + SUPPORTED_OPTIONS_REQ
+    for option_factory in option_factories:
+        option = option_factory()
+        parser.add_option(option)
+
+    # By default optparse sys.exits on parsing errors. We want to wrap
+    # that in our own exception.
+    def parser_exit(self, msg):
+        raise RequirementsFileParseError(msg)
+    parser.exit = parser_exit
+
+    return parser
+
+
+def join_lines(lines_enum):
+    """Joins a line ending in '\' with the previous line (except when following
+    comments).  The joined line takes on the index of the first line.
+    """
+    primary_line_number = None
+    new_line = []
+    for line_number, line in lines_enum:
+        if not line.endswith('\\') or COMMENT_RE.match(line):
+            if COMMENT_RE.match(line):
+                # this ensures comments are always matched later
+                line = ' ' + line
+            if new_line:
+                new_line.append(line)
+                yield primary_line_number, ''.join(new_line)
+                new_line = []
+            else:
+                yield line_number, line
+        else:
+            if not new_line:
+                primary_line_number = line_number
+            new_line.append(line.strip('\\'))
+
+    # last line contains \
+    if new_line:
+        yield primary_line_number, ''.join(new_line)
+
+    # TODO: handle space after '\'.
+
+
+def ignore_comments(lines_enum):
+    """
+    Strips comments and filter empty lines.
+    """
+    for line_number, line in lines_enum:
+        line = COMMENT_RE.sub('', line)
+        line = line.strip()
+        if line:
+            yield line_number, line
+
+
+def skip_regex(lines_enum, options):
+    """
+    Skip lines that match '--skip-requirements-regex' pattern
+
+    Note: the regex pattern is only built once
+    """
+    skip_regex = options.skip_requirements_regex if options else None
+    if skip_regex:
+        pattern = re.compile(skip_regex)
+        lines_enum = filterfalse(
+            lambda e: pattern.search(e[1]),
+            lines_enum)
+    return lines_enum
diff --git a/lib/python2.7/site-packages/pip/req/req_install.py b/lib/python2.7/site-packages/pip/req/req_install.py
new file mode 100644
index 0000000..1a98f37
--- /dev/null
+++ b/lib/python2.7/site-packages/pip/req/req_install.py
@@ -0,0 +1,1204 @@
+from __future__ import absolute_import
+
+import logging
+import os
+import re
+import shutil
+import sys
+import tempfile
+import traceback
+import warnings
+import zipfile
+
+from distutils import sysconfig
+from distutils.util import change_root
+from email.parser import FeedParser
+
+from pip._vendor import pkg_resources, six
+from pip._vendor.packaging import specifiers
+from pip._vendor.packaging.markers import Marker
+from pip._vendor.packaging.requirements import InvalidRequirement, Requirement
+from pip._vendor.packaging.utils import canonicalize_name
+from pip._vendor.packaging.version import Version, parse as parse_version
+from pip._vendor.six.moves import configparser
+
+import pip.wheel
+
+from pip.compat import native_str, get_stdlib, WINDOWS
+from pip.download import is_url, url_to_path, path_to_url, is_archive_file
+from pip.exceptions import (
+    InstallationError, UninstallationError,
+)
+from pip.locations import (
+    bin_py, running_under_virtualenv, PIP_DELETE_MARKER_FILENAME, bin_user,
+)
+from pip.utils import (
+    display_path, rmtree, ask_path_exists, backup_dir, is_installable_dir,
+    dist_in_usersite, dist_in_site_packages, egg_link_path,
+    call_subprocess, read_text_file, FakeFile, _make_build_dir, ensure_dir,
+    get_installed_version, normalize_path, dist_is_local,
+)
+
+from pip.utils.hashes import Hashes
+from pip.utils.deprecation import RemovedInPip10Warning
+from pip.utils.logging import indent_log
+from pip.utils.setuptools_build import SETUPTOOLS_SHIM
+from pip.utils.ui import open_spinner
+from pip.req.req_uninstall import UninstallPathSet
+from pip.vcs import vcs
+from pip.wheel import move_wheel_files, Wheel
+
+
+logger = logging.getLogger(__name__)
+
+operators = specifiers.Specifier._operators.keys()
+
+
+def _strip_extras(path):
+    m = re.match(r'^(.+)(\[[^\]]+\])$', path)
+    extras = None
+    if m:
+        path_no_extras = m.group(1)
+        extras = m.group(2)
+    else:
+        path_no_extras = path
+
+    return path_no_extras, extras
+
+
+def _safe_extras(extras):
+    return set(pkg_resources.safe_extra(extra) for extra in extras)
+
+
+class InstallRequirement(object):
+
+    def __init__(self, req, comes_from, source_dir=None, editable=False,
+                 link=None, as_egg=False, update=True,
+                 pycompile=True, markers=None, isolated=False, options=None,
+                 wheel_cache=None, constraint=False):
+        self.extras = ()
+        if isinstance(req, six.string_types):
+            try:
+                req = Requirement(req)
+            except InvalidRequirement:
+                if os.path.sep in req:
+                    add_msg = "It looks like a path. Does it exist ?"
+                elif '=' in req and not any(op in req for op in operators):
+                    add_msg = "= is not a valid operator. Did you mean == ?"
+                else:
+                    add_msg = traceback.format_exc()
+                raise InstallationError(
+                    "Invalid requirement: '%s'\n%s" % (req, add_msg))
+            self.extras = _safe_extras(req.extras)
+
+        self.req = req
+        self.comes_from = comes_from
+        self.constraint = constraint
+        self.source_dir = source_dir
+        self.editable = editable
+
+        self._wheel_cache = wheel_cache
+        self.link = self.original_link = link
+        self.as_egg = as_egg
+        if markers is not None:
+            self.markers = markers
+        else:
+            self.markers = req and req.marker
+        self._egg_info_path = None
+        # This holds the pkg_resources.Distribution object if this requirement
+        # is already available:
+        self.satisfied_by = None
+        # This hold the pkg_resources.Distribution object if this requirement
+        # conflicts with another installed distribution:
+        self.conflicts_with = None
+        # Temporary build location
+        self._temp_build_dir = None
+        # Used to store the global directory where the _temp_build_dir should
+        # have been created. Cf _correct_build_location method.
+        self._ideal_build_dir = None
+        # True if the editable should be updated:
+        self.update = update
+        # Set to True after successful installation
+        self.install_succeeded = None
+        # UninstallPathSet of uninstalled distribution (for possible rollback)
+        self.uninstalled = None
+        # Set True if a legitimate do-nothing-on-uninstall has happened - e.g.
+        # system site packages, stdlib packages.
+        self.nothing_to_uninstall = False
+        self.use_user_site = False
+        self.target_dir = None
+        self.options = options if options else {}
+        self.pycompile = pycompile
+        # Set to True after successful preparation of this requirement
+        self.prepared = False
+
+        self.isolated = isolated
+
+    @classmethod
+    def from_editable(cls, editable_req, comes_from=None, default_vcs=None,
+                      isolated=False, options=None, wheel_cache=None,
+                      constraint=False):
+        from pip.index import Link
+
+        name, url, extras_override = parse_editable(
+            editable_req, default_vcs)
+        if url.startswith('file:'):
+            source_dir = url_to_path(url)
+        else:
+            source_dir = None
+
+        res = cls(name, comes_from, source_dir=source_dir,
+                  editable=True,
+                  link=Link(url),
+                  constraint=constraint,
+                  isolated=isolated,
+                  options=options if options else {},
+                  wheel_cache=wheel_cache)
+
+        if extras_override is not None:
+            res.extras = _safe_extras(extras_override)
+
+        return res
+
+    @classmethod
+    def from_line(
+            cls, name, comes_from=None, isolated=False, options=None,
+            wheel_cache=None, constraint=False):
+        """Creates an InstallRequirement from a name, which might be a
+        requirement, directory containing 'setup.py', filename, or URL.
+        """
+        from pip.index import Link
+
+        if is_url(name):
+            marker_sep = '; '
+        else:
+            marker_sep = ';'
+        if marker_sep in name:
+            name, markers = name.split(marker_sep, 1)
+            markers = markers.strip()
+            if not markers:
+                markers = None
+            else:
+                markers = Marker(markers)
+        else:
+            markers = None
+        name = name.strip()
+        req = None
+        path = os.path.normpath(os.path.abspath(name))
+        link = None
+        extras = None
+
+        if is_url(name):
+            link = Link(name)
+        else:
+            p, extras = _strip_extras(path)
+            if (os.path.isdir(p) and
+                    (os.path.sep in name or name.startswith('.'))):
+
+                if not is_installable_dir(p):
+                    raise InstallationError(
+                        "Directory %r is not installable. File 'setup.py' "
+                        "not found." % name
+                    )
+                link = Link(path_to_url(p))
+            elif is_archive_file(p):
+                if not os.path.isfile(p):
+                    logger.warning(
+                        'Requirement %r looks like a filename, but the '
+                        'file does not exist',
+                        name
+                    )
+                link = Link(path_to_url(p))
+
+        # it's a local file, dir, or url
+        if link:
+            # Handle relative file URLs
+            if link.scheme == 'file' and re.search(r'\.\./', link.url):
+                link = Link(
+                    path_to_url(os.path.normpath(os.path.abspath(link.path))))
+            # wheel file
+            if link.is_wheel:
+                wheel = Wheel(link.filename)  # can raise InvalidWheelFilename
+                req = "%s==%s" % (wheel.name, wheel.version)
+            else:
+                # set the req to the egg fragment.  when it's not there, this
+                # will become an 'unnamed' requirement
+                req = link.egg_fragment
+
+        # a requirement specifier
+        else:
+            req = name
+
+        options = options if options else {}
+        res = cls(req, comes_from, link=link, markers=markers,
+                  isolated=isolated, options=options,
+                  wheel_cache=wheel_cache, constraint=constraint)
+
+        if extras:
+            res.extras = _safe_extras(
+                Requirement('placeholder' + extras).extras)
+
+        return res
+
+    def __str__(self):
+        if self.req:
+            s = str(self.req)
+            if self.link:
+                s += ' from %s' % self.link.url
+        else:
+            s = self.link.url if self.link else None
+        if self.satisfied_by is not None:
+            s += ' in %s' % display_path(self.satisfied_by.location)
+        if self.comes_from:
+            if isinstance(self.comes_from, six.string_types):
+                comes_from = self.comes_from
+            else:
+                comes_from = self.comes_from.from_path()
+            if comes_from:
+                s += ' (from %s)' % comes_from
+        return s
+
+    def __repr__(self):
+        return '<%s object: %s editable=%r>' % (
+            self.__class__.__name__, str(self), self.editable)
+
+    def populate_link(self, finder, upgrade, require_hashes):
+        """Ensure that if a link can be found for this, that it is found.
+
+        Note that self.link may still be None - if Upgrade is False and the
+        requirement is already installed.
+
+        If require_hashes is True, don't use the wheel cache, because cached
+        wheels, always built locally, have different hashes than the files
+        downloaded from the index server and thus throw false hash mismatches.
+        Furthermore, cached wheels at present have undeterministic contents due
+        to file modification times.
+        """
+        if self.link is None:
+            self.link = finder.find_requirement(self, upgrade)
+        if self._wheel_cache is not None and not require_hashes:
+            old_link = self.link
+            self.link = self._wheel_cache.cached_wheel(self.link, self.name)
+            if old_link != self.link:
+                logger.debug('Using cached wheel link: %s', self.link)
+
+    @property
+    def specifier(self):
+        return self.req.specifier
+
+    @property
+    def is_pinned(self):
+        """Return whether I am pinned to an exact version.
+
+        For example, some-package==1.2 is pinned; some-package>1.2 is not.
+        """
+        specifiers = self.specifier
+        return (len(specifiers) == 1 and
+                next(iter(specifiers)).operator in ('==', '==='))
+
+    def from_path(self):
+        if self.req is None:
+            return None
+        s = str(self.req)
+        if self.comes_from:
+            if isinstance(self.comes_from, six.string_types):
+                comes_from = self.comes_from
+            else:
+                comes_from = self.comes_from.from_path()
+            if comes_from:
+                s += '->' + comes_from
+        return s
+
+    def build_location(self, build_dir):
+        if self._temp_build_dir is not None:
+            return self._temp_build_dir
+        if self.req is None:
+            # for requirement via a path to a directory: the name of the
+            # package is not available yet so we create a temp directory
+            # Once run_egg_info will have run, we'll be able
+            # to fix it via _correct_build_location
+            # Some systems have /tmp as a symlink which confuses custom
+            # builds (such as numpy). Thus, we ensure that the real path
+            # is returned.
+            self._temp_build_dir = os.path.realpath(
+                tempfile.mkdtemp('-build', 'pip-')
+            )
+            self._ideal_build_dir = build_dir
+            return self._temp_build_dir
+        if self.editable:
+            name = self.name.lower()
+        else:
+            name = self.name
+        # FIXME: Is there a better place to create the build_dir? (hg and bzr
+        # need this)
+        if not os.path.exists(build_dir):
+            logger.debug('Creating directory %s', build_dir)
+            _make_build_dir(build_dir)
+        return os.path.join(build_dir, name)
+
+    def _correct_build_location(self):
+        """Move self._temp_build_dir to self._ideal_build_dir/self.req.name
+
+        For some requirements (e.g. a path to a directory), the name of the
+        package is not available until we run egg_info, so the build_location
+        will return a temporary directory and store the _ideal_build_dir.
+
+        This is only called by self.egg_info_path to fix the temporary build
+        directory.
+        """
+        if self.source_dir is not None:
+            return
+        assert self.req is not None
+        assert self._temp_build_dir
+        assert self._ideal_build_dir
+        old_location = self._temp_build_dir
+        self._temp_build_dir = None
+        new_location = self.build_location(self._ideal_build_dir)
+        if os.path.exists(new_location):
+            raise InstallationError(
+                'A package already exists in %s; please remove it to continue'
+                % display_path(new_location))
+        logger.debug(
+            'Moving package %s from %s to new location %s',
+            self, display_path(old_location), display_path(new_location),
+        )
+        shutil.move(old_location, new_location)
+        self._temp_build_dir = new_location
+        self._ideal_build_dir = None
+        self.source_dir = new_location
+        self._egg_info_path = None
+
+    @property
+    def name(self):
+        if self.req is None:
+            return None
+        return native_str(pkg_resources.safe_name(self.req.name))
+
+    @property
+    def setup_py_dir(self):
+        return os.path.join(
+            self.source_dir,
+            self.link and self.link.subdirectory_fragment or '')
+
+    @property
+    def setup_py(self):
+        assert self.source_dir, "No source dir for %s" % self
+        try:
+            import setuptools  # noqa
+        except ImportError:
+            if get_installed_version('setuptools') is None:
+                add_msg = "Please install setuptools."
+            else:
+                add_msg = traceback.format_exc()
+            # Setuptools is not available
+            raise InstallationError(
+                "Could not import setuptools which is required to "
+                "install from a source distribution.\n%s" % add_msg
+            )
+
+        setup_py = os.path.join(self.setup_py_dir, 'setup.py')
+
+        # Python2 __file__ should not be unicode
+        if six.PY2 and isinstance(setup_py, six.text_type):
+            setup_py = setup_py.encode(sys.getfilesystemencoding())
+
+        return setup_py
+
+    def run_egg_info(self):
+        assert self.source_dir
+        if self.name:
+            logger.debug(
+                'Running setup.py (path:%s) egg_info for package %s',
+                self.setup_py, self.name,
+            )
+        else:
+            logger.debug(
+                'Running setup.py (path:%s) egg_info for package from %s',
+                self.setup_py, self.link,
+            )
+
+        with indent_log():
+            script = SETUPTOOLS_SHIM % self.setup_py
+            base_cmd = [sys.executable, '-c', script]
+            if self.isolated:
+                base_cmd += ["--no-user-cfg"]
+            egg_info_cmd = base_cmd + ['egg_info']
+            # We can't put the .egg-info files at the root, because then the
+            # source code will be mistaken for an installed egg, causing
+            # problems
+            if self.editable:
+                egg_base_option = []
+            else:
+                egg_info_dir = os.path.join(self.setup_py_dir, 'pip-egg-info')
+                ensure_dir(egg_info_dir)
+                egg_base_option = ['--egg-base', 'pip-egg-info']
+            call_subprocess(
+                egg_info_cmd + egg_base_option,
+                cwd=self.setup_py_dir,
+                show_stdout=False,
+                command_desc='python setup.py egg_info')
+
+        if not self.req:
+            if isinstance(parse_version(self.pkg_info()["Version"]), Version):
+                op = "=="
+            else:
+                op = "==="
+            self.req = Requirement(
+                "".join([
+                    self.pkg_info()["Name"],
+                    op,
+                    self.pkg_info()["Version"],
+                ])
+            )
+            self._correct_build_location()
+        else:
+            metadata_name = canonicalize_name(self.pkg_info()["Name"])
+            if canonicalize_name(self.req.name) != metadata_name:
+                logger.warning(
+                    'Running setup.py (path:%s) egg_info for package %s '
+                    'produced metadata for project name %s. Fix your '
+                    '#egg=%s fragments.',
+                    self.setup_py, self.name, metadata_name, self.name
+                )
+                self.req = Requirement(metadata_name)
+
+    def egg_info_data(self, filename):
+        if self.satisfied_by is not None:
+            if not self.satisfied_by.has_metadata(filename):
+                return None
+            return self.satisfied_by.get_metadata(filename)
+        assert self.source_dir
+        filename = self.egg_info_path(filename)
+        if not os.path.exists(filename):
+            return None
+        data = read_text_file(filename)
+        return data
+
+    def egg_info_path(self, filename):
+        if self._egg_info_path is None:
+            if self.editable:
+                base = self.source_dir
+            else:
+                base = os.path.join(self.setup_py_dir, 'pip-egg-info')
+            filenames = os.listdir(base)
+            if self.editable:
+                filenames = []
+                for root, dirs, files in os.walk(base):
+                    for dir in vcs.dirnames:
+                        if dir in dirs:
+                            dirs.remove(dir)
+                    # Iterate over a copy of ``dirs``, since mutating
+                    # a list while iterating over it can cause trouble.
+                    # (See https://github.com/pypa/pip/pull/462.)
+                    for dir in list(dirs):
+                        # Don't search in anything that looks like a virtualenv
+                        # environment
+                        if (
+                                os.path.lexists(
+                                    os.path.join(root, dir, 'bin', 'python')
+                                ) or
+                                os.path.exists(
+                                    os.path.join(
+                                        root, dir, 'Scripts', 'Python.exe'
+                                    )
+                                )):
+                            dirs.remove(dir)
+                        # Also don't search through tests
+                        elif dir == 'test' or dir == 'tests':
+                            dirs.remove(dir)
+                    filenames.extend([os.path.join(root, dir)
+                                     for dir in dirs])
+                filenames = [f for f in filenames if f.endswith('.egg-info')]
+
+            if not filenames:
+                raise InstallationError(
+                    'No files/directories in %s (from %s)' % (base, filename)
+                )
+            assert filenames, \
+                "No files/directories in %s (from %s)" % (base, filename)
+
+            # if we have more than one match, we pick the toplevel one.  This
+            # can easily be the case if there is a dist folder which contains
+            # an extracted tarball for testing purposes.
+            if len(filenames) > 1:
+                filenames.sort(
+                    key=lambda x: x.count(os.path.sep) +
+                    (os.path.altsep and x.count(os.path.altsep) or 0)
+                )
+            self._egg_info_path = os.path.join(base, filenames[0])
+        return os.path.join(self._egg_info_path, filename)
+
+    def pkg_info(self):
+        p = FeedParser()
+        data = self.egg_info_data('PKG-INFO')
+        if not data:
+            logger.warning(
+                'No PKG-INFO file found in %s',
+                display_path(self.egg_info_path('PKG-INFO')),
+            )
+        p.feed(data or '')
+        return p.close()
+
+    _requirements_section_re = re.compile(r'\[(.*?)\]')
+
+    @property
+    def installed_version(self):
+        return get_installed_version(self.name)
+
+    def assert_source_matches_version(self):
+        assert self.source_dir
+        version = self.pkg_info()['version']
+        if self.req.specifier and version not in self.req.specifier:
+            logger.warning(
+                'Requested %s, but installing version %s',
+                self,
+                self.installed_version,
+            )
+        else:
+            logger.debug(
+                'Source in %s has version %s, which satisfies requirement %s',
+                display_path(self.source_dir),
+                version,
+                self,
+            )
+
+    def update_editable(self, obtain=True):
+        if not self.link:
+            logger.debug(
+                "Cannot update repository at %s; repository location is "
+                "unknown",
+                self.source_dir,
+            )
+            return
+        assert self.editable
+        assert self.source_dir
+        if self.link.scheme == 'file':
+            # Static paths don't get updated
+            return
+        assert '+' in self.link.url, "bad url: %r" % self.link.url
+        if not self.update:
+            return
+        vc_type, url = self.link.url.split('+', 1)
+        backend = vcs.get_backend(vc_type)
+        if backend:
+            vcs_backend = backend(self.link.url)
+            if obtain:
+                vcs_backend.obtain(self.source_dir)
+            else:
+                vcs_backend.export(self.source_dir)
+        else:
+            assert 0, (
+                'Unexpected version control type (in %s): %s'
+                % (self.link, vc_type))
+
+    def uninstall(self, auto_confirm=False):
+        """
+        Uninstall the distribution currently satisfying this requirement.
+
+        Prompts before removing or modifying files unless
+        ``auto_confirm`` is True.
+
+        Refuses to delete or modify files outside of ``sys.prefix`` -
+        thus uninstallation within a virtual environment can only
+        modify that virtual environment, even if the virtualenv is
+        linked to global site-packages.
+
+        """
+        if not self.check_if_exists():
+            raise UninstallationError(
+                "Cannot uninstall requirement %s, not installed" % (self.name,)
+            )
+        dist = self.satisfied_by or self.conflicts_with
+
+        dist_path = normalize_path(dist.location)
+        if not dist_is_local(dist):
+            logger.info(
+                "Not uninstalling %s at %s, outside environment %s",
+                dist.key,
+                dist_path,
+                sys.prefix,
+            )
+            self.nothing_to_uninstall = True
+            return
+
+        if dist_path in get_stdlib():
+            logger.info(
+                "Not uninstalling %s at %s, as it is in the standard library.",
+                dist.key,
+                dist_path,
+            )
+            self.nothing_to_uninstall = True
+            return
+
+        paths_to_remove = UninstallPathSet(dist)
+        develop_egg_link = egg_link_path(dist)
+        develop_egg_link_egg_info = '{0}.egg-info'.format(
+            pkg_resources.to_filename(dist.project_name))
+        egg_info_exists = dist.egg_info and os.path.exists(dist.egg_info)
+        # Special case for distutils installed package
+        distutils_egg_info = getattr(dist._provider, 'path', None)
+
+        # Uninstall cases order do matter as in the case of 2 installs of the
+        # same package, pip needs to uninstall the currently detected version
+        if (egg_info_exists and dist.egg_info.endswith('.egg-info') and
+                not dist.egg_info.endswith(develop_egg_link_egg_info)):
+            # if dist.egg_info.endswith(develop_egg_link_egg_info), we
+            # are in fact in the develop_egg_link case
+            paths_to_remove.add(dist.egg_info)
+            if dist.has_metadata('installed-files.txt'):
+                for installed_file in dist.get_metadata(
+                        'installed-files.txt').splitlines():
+                    path = os.path.normpath(
+                        os.path.join(dist.egg_info, installed_file)
+                    )
+                    paths_to_remove.add(path)
+            # FIXME: need a test for this elif block
+            # occurs with --single-version-externally-managed/--record outside
+            # of pip
+            elif dist.has_metadata('top_level.txt'):
+                if dist.has_metadata('namespace_packages.txt'):
+                    namespaces = dist.get_metadata('namespace_packages.txt')
+                else:
+                    namespaces = []
+                for top_level_pkg in [
+                        p for p
+                        in dist.get_metadata('top_level.txt').splitlines()
+                        if p and p not in namespaces]:
+                    path = os.path.join(dist.location, top_level_pkg)
+                    paths_to_remove.add(path)
+                    paths_to_remove.add(path + '.py')
+                    paths_to_remove.add(path + '.pyc')
+                    paths_to_remove.add(path + '.pyo')
+
+        elif distutils_egg_info:
+            warnings.warn(
+                "Uninstalling a distutils installed project ({0}) has been "
+                "deprecated and will be removed in a future version. This is "
+                "due to the fact that uninstalling a distutils project will "
+                "only partially uninstall the project.".format(self.name),
+                RemovedInPip10Warning,
+            )
+            paths_to_remove.add(distutils_egg_info)
+
+        elif dist.location.endswith('.egg'):
+            # package installed by easy_install
+            # We cannot match on dist.egg_name because it can slightly vary
+            # i.e. setuptools-0.6c11-py2.6.egg vs setuptools-0.6rc11-py2.6.egg
+            paths_to_remove.add(dist.location)
+            easy_install_egg = os.path.split(dist.location)[1]
+            easy_install_pth = os.path.join(os.path.dirname(dist.location),
+                                            'easy-install.pth')
+            paths_to_remove.add_pth(easy_install_pth, './' + easy_install_egg)
+
+        elif egg_info_exists and dist.egg_info.endswith('.dist-info'):
+            for path in pip.wheel.uninstallation_paths(dist):
+                paths_to_remove.add(path)
+
+        elif develop_egg_link:
+            # develop egg
+            with open(develop_egg_link, 'r') as fh:
+                link_pointer = os.path.normcase(fh.readline().strip())
+            assert (link_pointer == dist.location), (
+                'Egg-link %s does not match installed location of %s '
+                '(at %s)' % (link_pointer, self.name, dist.location)
+            )
+            paths_to_remove.add(develop_egg_link)
+            easy_install_pth = os.path.join(os.path.dirname(develop_egg_link),
+                                            'easy-install.pth')
+            paths_to_remove.add_pth(easy_install_pth, dist.location)
+
+        else:
+            logger.debug(
+                'Not sure how to uninstall: %s - Check: %s',
+                dist, dist.location)
+
+        # find distutils scripts= scripts
+        if dist.has_metadata('scripts') and dist.metadata_isdir('scripts'):
+            for script in dist.metadata_listdir('scripts'):
+                if dist_in_usersite(dist):
+                    bin_dir = bin_user
+                else:
+                    bin_dir = bin_py
+                paths_to_remove.add(os.path.join(bin_dir, script))
+                if WINDOWS:
+                    paths_to_remove.add(os.path.join(bin_dir, script) + '.bat')
+
+        # find console_scripts
+        if dist.has_metadata('entry_points.txt'):
+            if six.PY2:
+                options = {}
+            else:
+                options = {"delimiters": ('=', )}
+            config = configparser.SafeConfigParser(**options)
+            config.readfp(
+                FakeFile(dist.get_metadata_lines('entry_points.txt'))
+            )
+            if config.has_section('console_scripts'):
+                for name, value in config.items('console_scripts'):
+                    if dist_in_usersite(dist):
+                        bin_dir = bin_user
+                    else:
+                        bin_dir = bin_py
+                    paths_to_remove.add(os.path.join(bin_dir, name))
+                    if WINDOWS:
+                        paths_to_remove.add(
+                            os.path.join(bin_dir, name) + '.exe'
+                        )
+                        paths_to_remove.add(
+                            os.path.join(bin_dir, name) + '.exe.manifest'
+                        )
+                        paths_to_remove.add(
+                            os.path.join(bin_dir, name) + '-script.py'
+                        )
+
+        paths_to_remove.remove(auto_confirm)
+        self.uninstalled = paths_to_remove
+
+    def rollback_uninstall(self):
+        if self.uninstalled:
+            self.uninstalled.rollback()
+        else:
+            logger.error(
+                "Can't rollback %s, nothing uninstalled.", self.name,
+            )
+
+    def commit_uninstall(self):
+        if self.uninstalled:
+            self.uninstalled.commit()
+        elif not self.nothing_to_uninstall:
+            logger.error(
+                "Can't commit %s, nothing uninstalled.", self.name,
+            )
+
+    def archive(self, build_dir):
+        assert self.source_dir
+        create_archive = True
+        archive_name = '%s-%s.zip' % (self.name, self.pkg_info()["version"])
+        archive_path = os.path.join(build_dir, archive_name)
+        if os.path.exists(archive_path):
+            response = ask_path_exists(
+                'The file %s exists. (i)gnore, (w)ipe, (b)ackup, (a)bort ' %
+                display_path(archive_path), ('i', 'w', 'b', 'a'))
+            if response == 'i':
+                create_archive = False
+            elif response == 'w':
+                logger.warning('Deleting %s', display_path(archive_path))
+                os.remove(archive_path)
+            elif response == 'b':
+                dest_file = backup_dir(archive_path)
+                logger.warning(
+                    'Backing up %s to %s',
+                    display_path(archive_path),
+                    display_path(dest_file),
+                )
+                shutil.move(archive_path, dest_file)
+            elif response == 'a':
+                sys.exit(-1)
+        if create_archive:
+            zip = zipfile.ZipFile(
+                archive_path, 'w', zipfile.ZIP_DEFLATED,
+                allowZip64=True
+            )
+            dir = os.path.normcase(os.path.abspath(self.setup_py_dir))
+            for dirpath, dirnames, filenames in os.walk(dir):
+                if 'pip-egg-info' in dirnames:
+                    dirnames.remove('pip-egg-info')
+                for dirname in dirnames:
+                    dirname = os.path.join(dirpath, dirname)
+                    name = self._clean_zip_name(dirname, dir)
+                    zipdir = zipfile.ZipInfo(self.name + '/' + name + '/')
+                    zipdir.external_attr = 0x1ED << 16  # 0o755
+                    zip.writestr(zipdir, '')
+                for filename in filenames:
+                    if filename == PIP_DELETE_MARKER_FILENAME:
+                        continue
+                    filename = os.path.join(dirpath, filename)
+                    name = self._clean_zip_name(filename, dir)
+                    zip.write(filename, self.name + '/' + name)
+            zip.close()
+            logger.info('Saved %s', display_path(archive_path))
+
+    def _clean_zip_name(self, name, prefix):
+        assert name.startswith(prefix + os.path.sep), (
+            "name %r doesn't start with prefix %r" % (name, prefix)
+        )
+        name = name[len(prefix) + 1:]
+        name = name.replace(os.path.sep, '/')
+        return name
+
+    def match_markers(self, extras_requested=None):
+        if not extras_requested:
+            # Provide an extra to safely evaluate the markers
+            # without matching any extra
+            extras_requested = ('',)
+        if self.markers is not None:
+            return any(
+                self.markers.evaluate({'extra': extra})
+                for extra in extras_requested)
+        else:
+            return True
+
+    def install(self, install_options, global_options=[], root=None,
+                prefix=None):
+        if self.editable:
+            self.install_editable(
+                install_options, global_options, prefix=prefix)
+            return
+        if self.is_wheel:
+            version = pip.wheel.wheel_version(self.source_dir)
+            pip.wheel.check_compatibility(version, self.name)
+
+            self.move_wheel_files(self.source_dir, root=root, prefix=prefix)
+            self.install_succeeded = True
+            return
+
+        # Extend the list of global and install options passed on to
+        # the setup.py call with the ones from the requirements file.
+        # Options specified in requirements file override those
+        # specified on the command line, since the last option given
+        # to setup.py is the one that is used.
+        global_options += self.options.get('global_options', [])
+        install_options += self.options.get('install_options', [])
+
+        if self.isolated:
+            global_options = list(global_options) + ["--no-user-cfg"]
+
+        temp_location = tempfile.mkdtemp('-record', 'pip-')
+        record_filename = os.path.join(temp_location, 'install-record.txt')
+        try:
+            install_args = self.get_install_args(
+                global_options, record_filename, root, prefix)
+            msg = 'Running setup.py install for %s' % (self.name,)
+            with open_spinner(msg) as spinner:
+                with indent_log():
+                    call_subprocess(
+                        install_args + install_options,
+                        cwd=self.setup_py_dir,
+                        show_stdout=False,
+                        spinner=spinner,
+                    )
+
+            if not os.path.exists(record_filename):
+                logger.debug('Record file %s not found', record_filename)
+                return
+            self.install_succeeded = True
+            if self.as_egg:
+                # there's no --always-unzip option we can pass to install
+                # command so we unable to save the installed-files.txt
+                return
+
+            def prepend_root(path):
+                if root is None or not os.path.isabs(path):
+                    return path
+                else:
+                    return change_root(root, path)
+
+            with open(record_filename) as f:
+                for line in f:
+                    directory = os.path.dirname(line)
+                    if directory.endswith('.egg-info'):
+                        egg_info_dir = prepend_root(directory)
+                        break
+                else:
+                    logger.warning(
+                        'Could not find .egg-info directory in install record'
+                        ' for %s',
+                        self,
+                    )
+                    # FIXME: put the record somewhere
+                    # FIXME: should this be an error?
+                    return
+            new_lines = []
+            with open(record_filename) as f:
+                for line in f:
+                    filename = line.strip()
+                    if os.path.isdir(filename):
+                        filename += os.path.sep
+                    new_lines.append(
+                        os.path.relpath(
+                            prepend_root(filename), egg_info_dir)
+                    )
+            inst_files_path = os.path.join(egg_info_dir, 'installed-files.txt')
+            with open(inst_files_path, 'w') as f:
+                f.write('\n'.join(new_lines) + '\n')
+        finally:
+            if os.path.exists(record_filename):
+                os.remove(record_filename)
+            rmtree(temp_location)
+
+    def ensure_has_source_dir(self, parent_dir):
+        """Ensure that a source_dir is set.
+
+        This will create a temporary build dir if the name of the requirement
+        isn't known yet.
+
+        :param parent_dir: The ideal pip parent_dir for the source_dir.
+            Generally src_dir for editables and build_dir for sdists.
+        :return: self.source_dir
+        """
+        if self.source_dir is None:
+            self.source_dir = self.build_location(parent_dir)
+        return self.source_dir
+
+    def get_install_args(self, global_options, record_filename, root, prefix):
+        install_args = [sys.executable, "-u"]
+        install_args.append('-c')
+        install_args.append(SETUPTOOLS_SHIM % self.setup_py)
+        install_args += list(global_options) + \
+            ['install', '--record', record_filename]
+
+        if not self.as_egg:
+            install_args += ['--single-version-externally-managed']
+
+        if root is not None:
+            install_args += ['--root', root]
+        if prefix is not None:
+            install_args += ['--prefix', prefix]
+
+        if self.pycompile:
+            install_args += ["--compile"]
+        else:
+            install_args += ["--no-compile"]
+
+        if running_under_virtualenv():
+            py_ver_str = 'python' + sysconfig.get_python_version()
+            install_args += ['--install-headers',
+                             os.path.join(sys.prefix, 'include', 'site',
+                                          py_ver_str, self.name)]
+
+        return install_args
+
+    def remove_temporary_source(self):
+        """Remove the source files from this requirement, if they are marked
+        for deletion"""
+        if self.source_dir and os.path.exists(
+                os.path.join(self.source_dir, PIP_DELETE_MARKER_FILENAME)):
+            logger.debug('Removing source in %s', self.source_dir)
+            rmtree(self.source_dir)
+        self.source_dir = None
+        if self._temp_build_dir and os.path.exists(self._temp_build_dir):
+            rmtree(self._temp_build_dir)
+        self._temp_build_dir = None
+
+    def install_editable(self, install_options,
+                         global_options=(), prefix=None):
+        logger.info('Running setup.py develop for %s', self.name)
+
+        if self.isolated:
+            global_options = list(global_options) + ["--no-user-cfg"]
+
+        if prefix:
+            prefix_param = ['--prefix={0}'.format(prefix)]
+            install_options = list(install_options) + prefix_param
+
+        with indent_log():
+            # FIXME: should we do --install-headers here too?
+            call_subprocess(
+                [
+                    sys.executable,
+                    '-c',
+                    SETUPTOOLS_SHIM % self.setup_py
+                ] +
+                list(global_options) +
+                ['develop', '--no-deps'] +
+                list(install_options),
+
+                cwd=self.setup_py_dir,
+                show_stdout=False)
+
+        self.install_succeeded = True
+
+    def check_if_exists(self):
+        """Find an installed distribution that satisfies or conflicts
+        with this requirement, and set self.satisfied_by or
+        self.conflicts_with appropriately.
+        """
+        if self.req is None:
+            return False
+        try:
+            # get_distribution() will resolve the entire list of requirements
+            # anyway, and we've already determined that we need the requirement
+            # in question, so strip the marker so that we don't try to
+            # evaluate it.
+            no_marker = Requirement(str(self.req))
+            no_marker.marker = None
+            self.satisfied_by = pkg_resources.get_distribution(str(no_marker))
+            if self.editable and self.satisfied_by:
+                self.conflicts_with = self.satisfied_by
+                # when installing editables, nothing pre-existing should ever
+                # satisfy
+                self.satisfied_by = None
+                return True
+        except pkg_resources.DistributionNotFound:
+            return False
+        except pkg_resources.VersionConflict:
+            existing_dist = pkg_resources.get_distribution(
+                self.req.name
+            )
+            if self.use_user_site:
+                if dist_in_usersite(existing_dist):
+                    self.conflicts_with = existing_dist
+                elif (running_under_virtualenv() and
+                        dist_in_site_packages(existing_dist)):
+                    raise InstallationError(
+                        "Will not install to the user site because it will "
+                        "lack sys.path precedence to %s in %s" %
+                        (existing_dist.project_name, existing_dist.location)
+                    )
+            else:
+                self.conflicts_with = existing_dist
+        return True
+
+    @property
+    def is_wheel(self):
+        return self.link and self.link.is_wheel
+
+    def move_wheel_files(self, wheeldir, root=None, prefix=None):
+        move_wheel_files(
+            self.name, self.req, wheeldir,
+            user=self.use_user_site,
+            home=self.target_dir,
+            root=root,
+            prefix=prefix,
+            pycompile=self.pycompile,
+            isolated=self.isolated,
+        )
+
+    def get_dist(self):
+        """Return a pkg_resources.Distribution built from self.egg_info_path"""
+        egg_info = self.egg_info_path('').rstrip('/')
+        base_dir = os.path.dirname(egg_info)
+        metadata = pkg_resources.PathMetadata(base_dir, egg_info)
+        dist_name = os.path.splitext(os.path.basename(egg_info))[0]
+        return pkg_resources.Distribution(
+            os.path.dirname(egg_info),
+            project_name=dist_name,
+            metadata=metadata)
+
+    @property
+    def has_hash_options(self):
+        """Return whether any known-good hashes are specified as options.
+
+        These activate --require-hashes mode; hashes specified as part of a
+        URL do not.
+
+        """
+        return bool(self.options.get('hashes', {}))
+
+    def hashes(self, trust_internet=True):
+        """Return a hash-comparer that considers my option- and URL-based
+        hashes to be known-good.
+
+        Hashes in URLs--ones embedded in the requirements file, not ones
+        downloaded from an index server--are almost peers with ones from
+        flags. They satisfy --require-hashes (whether it was implicitly or
+        explicitly activated) but do not activate it. md5 and sha224 are not
+        allowed in flags, which should nudge people toward good algos. We
+        always OR all hashes together, even ones from URLs.
+
+        :param trust_internet: Whether to trust URL-based (#md5=...) hashes
+            downloaded from the internet, as by populate_link()
+
+        """
+        good_hashes = self.options.get('hashes', {}).copy()
+        link = self.link if trust_internet else self.original_link
+        if link and link.hash:
+            good_hashes.setdefault(link.hash_name, []).append(link.hash)
+        return Hashes(good_hashes)
+
+
+def _strip_postfix(req):
+    """
+        Strip req postfix ( -dev, 0.2, etc )
+    """
+    # FIXME: use package_to_requirement?
+    match = re.search(r'^(.*?)(?:-dev|-\d.*)$', req)
+    if match:
+        # Strip off -dev, -0.2, etc.
+        req = match.group(1)
+    return req
+
+
+def parse_editable(editable_req, default_vcs=None):
+    """Parses an editable requirement into:
+        - a requirement name
+        - an URL
+        - extras
+        - editable options
+    Accepted requirements:
+        svn+http://blahblah@rev#egg=Foobar[baz]&subdirectory=version_subdir
+        .[some_extra]
+    """
+
+    from pip.index import Link
+
+    url = editable_req
+    extras = None
+
+    # If a file path is specified with extras, strip off the extras.
+    m = re.match(r'^(.+)(\[[^\]]+\])$', url)
+    if m:
+        url_no_extras = m.group(1)
+        extras = m.group(2)
+    else:
+        url_no_extras = url
+
+    if os.path.isdir(url_no_extras):
+        if not os.path.exists(os.path.join(url_no_extras, 'setup.py')):
+            raise InstallationError(
+                "Directory %r is not installable. File 'setup.py' not found." %
+                url_no_extras
+            )
+        # Treating it as code that has already been checked out
+        url_no_extras = path_to_url(url_no_extras)
+
+    if url_no_extras.lower().startswith('file:'):
+        package_name = Link(url_no_extras).egg_fragment
+        if extras:
+            return (
+                package_name,
+                url_no_extras,
+                Requirement("placeholder" + extras.lower()).extras,
+            )
+        else:
+            return package_name, url_no_extras, None
+
+    for version_control in vcs:
+        if url.lower().startswith('%s:' % version_control):
+            url = '%s+%s' % (version_control, url)
+            break
+
+    if '+' not in url:
+        if default_vcs:
+            warnings.warn(
+                "--default-vcs has been deprecated and will be removed in "
+                "the future.",
+                RemovedInPip10Warning,
+            )
+            url = default_vcs + '+' + url
+        else:
+            raise InstallationError(
+                '%s should either be a path to a local project or a VCS url '
+                'beginning with svn+, git+, hg+, or bzr+' %
+                editable_req
+            )
+
+    vc_type = url.split('+', 1)[0].lower()
+
+    if not vcs.get_backend(vc_type):
+        error_message = 'For --editable=%s only ' % editable_req + \
+            ', '.join([backend.name + '+URL' for backend in vcs.backends]) + \
+            ' is currently supported'
+        raise InstallationError(error_message)
+
+    package_name = Link(url).egg_fragment
+    if not package_name:
+        raise InstallationError(
+            "Could not detect requirement name, please specify one with #egg="
+        )
+    if not package_name:
+        raise InstallationError(
+            '--editable=%s is not the right format; it must have '
+            '#egg=Package' % editable_req
+        )
+    return _strip_postfix(package_name), url, None
diff --git a/lib/python2.7/site-packages/pip/req/req_set.py b/lib/python2.7/site-packages/pip/req/req_set.py
new file mode 100644
index 0000000..76aec06
--- /dev/null
+++ b/lib/python2.7/site-packages/pip/req/req_set.py
@@ -0,0 +1,798 @@
+from __future__ import absolute_import
+
+from collections import defaultdict
+from itertools import chain
+import logging
+import os
+
+from pip._vendor import pkg_resources
+from pip._vendor import requests
+
+from pip.compat import expanduser
+from pip.download import (is_file_url, is_dir_url, is_vcs_url, url_to_path,
+                          unpack_url)
+from pip.exceptions import (InstallationError, BestVersionAlreadyInstalled,
+                            DistributionNotFound, PreviousBuildDirError,
+                            HashError, HashErrors, HashUnpinned,
+                            DirectoryUrlHashUnsupported, VcsHashUnsupported,
+                            UnsupportedPythonVersion)
+from pip.req.req_install import InstallRequirement
+from pip.utils import (
+    display_path, dist_in_usersite, ensure_dir, normalize_path)
+from pip.utils.hashes import MissingHashes
+from pip.utils.logging import indent_log
+from pip.utils.packaging import check_dist_requires_python
+from pip.vcs import vcs
+from pip.wheel import Wheel
+
+logger = logging.getLogger(__name__)
+
+
+class Requirements(object):
+
+    def __init__(self):
+        self._keys = []
+        self._dict = {}
+
+    def keys(self):
+        return self._keys
+
+    def values(self):
+        return [self._dict[key] for key in self._keys]
+
+    def __contains__(self, item):
+        return item in self._keys
+
+    def __setitem__(self, key, value):
+        if key not in self._keys:
+            self._keys.append(key)
+        self._dict[key] = value
+
+    def __getitem__(self, key):
+        return self._dict[key]
+
+    def __repr__(self):
+        values = ['%s: %s' % (repr(k), repr(self[k])) for k in self.keys()]
+        return 'Requirements({%s})' % ', '.join(values)
+
+
+class DistAbstraction(object):
+    """Abstracts out the wheel vs non-wheel prepare_files logic.
+
+    The requirements for anything installable are as follows:
+     - we must be able to determine the requirement name
+       (or we can't correctly handle the non-upgrade case).
+     - we must be able to generate a list of run-time dependencies
+       without installing any additional packages (or we would
+       have to either burn time by doing temporary isolated installs
+       or alternatively violate pips 'don't start installing unless
+       all requirements are available' rule - neither of which are
+       desirable).
+     - for packages with setup requirements, we must also be able
+       to determine their requirements without installing additional
+       packages (for the same reason as run-time dependencies)
+     - we must be able to create a Distribution object exposing the
+       above metadata.
+    """
+
+    def __init__(self, req_to_install):
+        self.req_to_install = req_to_install
+
+    def dist(self, finder):
+        """Return a setuptools Dist object."""
+        raise NotImplementedError(self.dist)
+
+    def prep_for_dist(self):
+        """Ensure that we can get a Dist for this requirement."""
+        raise NotImplementedError(self.dist)
+
+
+def make_abstract_dist(req_to_install):
+    """Factory to make an abstract dist object.
+
+    Preconditions: Either an editable req with a source_dir, or satisfied_by or
+    a wheel link, or a non-editable req with a source_dir.
+
+    :return: A concrete DistAbstraction.
+    """
+    if req_to_install.editable:
+        return IsSDist(req_to_install)
+    elif req_to_install.link and req_to_install.link.is_wheel:
+        return IsWheel(req_to_install)
+    else:
+        return IsSDist(req_to_install)
+
+
+class IsWheel(DistAbstraction):
+
+    def dist(self, finder):
+        return list(pkg_resources.find_distributions(
+            self.req_to_install.source_dir))[0]
+
+    def prep_for_dist(self):
+        # FIXME:https://github.com/pypa/pip/issues/1112
+        pass
+
+
+class IsSDist(DistAbstraction):
+
+    def dist(self, finder):
+        dist = self.req_to_install.get_dist()
+        # FIXME: shouldn't be globally added:
+        if dist.has_metadata('dependency_links.txt'):
+            finder.add_dependency_links(
+                dist.get_metadata_lines('dependency_links.txt')
+            )
+        return dist
+
+    def prep_for_dist(self):
+        self.req_to_install.run_egg_info()
+        self.req_to_install.assert_source_matches_version()
+
+
+class Installed(DistAbstraction):
+
+    def dist(self, finder):
+        return self.req_to_install.satisfied_by
+
+    def prep_for_dist(self):
+        pass
+
+
+class RequirementSet(object):
+
+    def __init__(self, build_dir, src_dir, download_dir, upgrade=False,
+                 upgrade_strategy=None, ignore_installed=False, as_egg=False,
+                 target_dir=None, ignore_dependencies=False,
+                 force_reinstall=False, use_user_site=False, session=None,
+                 pycompile=True, isolated=False, wheel_download_dir=None,
+                 wheel_cache=None, require_hashes=False,
+                 ignore_requires_python=False):
+        """Create a RequirementSet.
+
+        :param wheel_download_dir: Where still-packed .whl files should be
+            written to. If None they are written to the download_dir parameter.
+            Separate to download_dir to permit only keeping wheel archives for
+            pip wheel.
+        :param download_dir: Where still packed archives should be written to.
+            If None they are not saved, and are deleted immediately after
+            unpacking.
+        :param wheel_cache: The pip wheel cache, for passing to
+            InstallRequirement.
+        """
+        if session is None:
+            raise TypeError(
+                "RequirementSet() missing 1 required keyword argument: "
+                "'session'"
+            )
+
+        self.build_dir = build_dir
+        self.src_dir = src_dir
+        # XXX: download_dir and wheel_download_dir overlap semantically and may
+        # be combined if we're willing to have non-wheel archives present in
+        # the wheelhouse output by 'pip wheel'.
+        self.download_dir = download_dir
+        self.upgrade = upgrade
+        self.upgrade_strategy = upgrade_strategy
+        self.ignore_installed = ignore_installed
+        self.force_reinstall = force_reinstall
+        self.requirements = Requirements()
+        # Mapping of alias: real_name
+        self.requirement_aliases = {}
+        self.unnamed_requirements = []
+        self.ignore_dependencies = ignore_dependencies
+        self.ignore_requires_python = ignore_requires_python
+        self.successfully_downloaded = []
+        self.successfully_installed = []
+        self.reqs_to_cleanup = []
+        self.as_egg = as_egg
+        self.use_user_site = use_user_site
+        self.target_dir = target_dir  # set from --target option
+        self.session = session
+        self.pycompile = pycompile
+        self.isolated = isolated
+        if wheel_download_dir:
+            wheel_download_dir = normalize_path(wheel_download_dir)
+        self.wheel_download_dir = wheel_download_dir
+        self._wheel_cache = wheel_cache
+        self.require_hashes = require_hashes
+        # Maps from install_req -> dependencies_of_install_req
+        self._dependencies = defaultdict(list)
+
+    def __str__(self):
+        reqs = [req for req in self.requirements.values()
+                if not req.comes_from]
+        reqs.sort(key=lambda req: req.name.lower())
+        return ' '.join([str(req.req) for req in reqs])
+
+    def __repr__(self):
+        reqs = [req for req in self.requirements.values()]
+        reqs.sort(key=lambda req: req.name.lower())
+        reqs_str = ', '.join([str(req.req) for req in reqs])
+        return ('<%s object; %d requirement(s): %s>'
+                % (self.__class__.__name__, len(reqs), reqs_str))
+
+    def add_requirement(self, install_req, parent_req_name=None,
+                        extras_requested=None):
+        """Add install_req as a requirement to install.
+
+        :param parent_req_name: The name of the requirement that needed this
+            added. The name is used because when multiple unnamed requirements
+            resolve to the same name, we could otherwise end up with dependency
+            links that point outside the Requirements set. parent_req must
+            already be added. Note that None implies that this is a user
+            supplied requirement, vs an inferred one.
+        :param extras_requested: an iterable of extras used to evaluate the
+            environement markers.
+        :return: Additional requirements to scan. That is either [] if
+            the requirement is not applicable, or [install_req] if the
+            requirement is applicable and has just been added.
+        """
+        name = install_req.name
+        if not install_req.match_markers(extras_requested):
+            logger.warning("Ignoring %s: markers '%s' don't match your "
+                           "environment", install_req.name,
+                           install_req.markers)
+            return []
+
+        # This check has to come after we filter requirements with the
+        # environment markers.
+        if install_req.link and install_req.link.is_wheel:
+            wheel = Wheel(install_req.link.filename)
+            if not wheel.supported():
+                raise InstallationError(
+                    "%s is not a supported wheel on this platform." %
+                    wheel.filename
+                )
+
+        install_req.as_egg = self.as_egg
+        install_req.use_user_site = self.use_user_site
+        install_req.target_dir = self.target_dir
+        install_req.pycompile = self.pycompile
+        install_req.is_direct = (parent_req_name is None)
+
+        if not name:
+            # url or path requirement w/o an egg fragment
+            self.unnamed_requirements.append(install_req)
+            return [install_req]
+        else:
+            try:
+                existing_req = self.get_requirement(name)
+            except KeyError:
+                existing_req = None
+            if (parent_req_name is None and existing_req and not
+                    existing_req.constraint and
+                    existing_req.extras == install_req.extras and not
+                    existing_req.req.specifier == install_req.req.specifier):
+                raise InstallationError(
+                    'Double requirement given: %s (already in %s, name=%r)'
+                    % (install_req, existing_req, name))
+            if not existing_req:
+                # Add requirement
+                self.requirements[name] = install_req
+                # FIXME: what about other normalizations?  E.g., _ vs. -?
+                if name.lower() != name:
+                    self.requirement_aliases[name.lower()] = name
+                result = [install_req]
+            else:
+                # Assume there's no need to scan, and that we've already
+                # encountered this for scanning.
+                result = []
+                if not install_req.constraint and existing_req.constraint:
+                    if (install_req.link and not (existing_req.link and
+                       install_req.link.path == existing_req.link.path)):
+                        self.reqs_to_cleanup.append(install_req)
+                        raise InstallationError(
+                            "Could not satisfy constraints for '%s': "
+                            "installation from path or url cannot be "
+                            "constrained to a version" % name)
+                    # If we're now installing a constraint, mark the existing
+                    # object for real installation.
+                    existing_req.constraint = False
+                    existing_req.extras = tuple(
+                        sorted(set(existing_req.extras).union(
+                               set(install_req.extras))))
+                    logger.debug("Setting %s extras to: %s",
+                                 existing_req, existing_req.extras)
+                    # And now we need to scan this.
+                    result = [existing_req]
+                # Canonicalise to the already-added object for the backref
+                # check below.
+                install_req = existing_req
+            if parent_req_name:
+                parent_req = self.get_requirement(parent_req_name)
+                self._dependencies[parent_req].append(install_req)
+            return result
+
+    def has_requirement(self, project_name):
+        name = project_name.lower()
+        if (name in self.requirements and
+           not self.requirements[name].constraint or
+           name in self.requirement_aliases and
+           not self.requirements[self.requirement_aliases[name]].constraint):
+            return True
+        return False
+
+    @property
+    def has_requirements(self):
+        return list(req for req in self.requirements.values() if not
+                    req.constraint) or self.unnamed_requirements
+
+    @property
+    def is_download(self):
+        if self.download_dir:
+            self.download_dir = expanduser(self.download_dir)
+            if os.path.exists(self.download_dir):
+                return True
+            else:
+                logger.critical('Could not find download directory')
+                raise InstallationError(
+                    "Could not find or access download directory '%s'"
+                    % display_path(self.download_dir))
+        return False
+
+    def get_requirement(self, project_name):
+        for name in project_name, project_name.lower():
+            if name in self.requirements:
+                return self.requirements[name]
+            if name in self.requirement_aliases:
+                return self.requirements[self.requirement_aliases[name]]
+        raise KeyError("No project with the name %r" % project_name)
+
+    def uninstall(self, auto_confirm=False):
+        for req in self.requirements.values():
+            if req.constraint:
+                continue
+            req.uninstall(auto_confirm=auto_confirm)
+            req.commit_uninstall()
+
+    def prepare_files(self, finder):
+        """
+        Prepare process. Create temp directories, download and/or unpack files.
+        """
+        # make the wheelhouse
+        if self.wheel_download_dir:
+            ensure_dir(self.wheel_download_dir)
+
+        # If any top-level requirement has a hash specified, enter
+        # hash-checking mode, which requires hashes from all.
+        root_reqs = self.unnamed_requirements + self.requirements.values()
+        require_hashes = (self.require_hashes or
+                          any(req.has_hash_options for req in root_reqs))
+        if require_hashes and self.as_egg:
+            raise InstallationError(
+                '--egg is not allowed with --require-hashes mode, since it '
+                'delegates dependency resolution to setuptools and could thus '
+                'result in installation of unhashed packages.')
+
+        # Actually prepare the files, and collect any exceptions. Most hash
+        # exceptions cannot be checked ahead of time, because
+        # req.populate_link() needs to be called before we can make decisions
+        # based on link type.
+        discovered_reqs = []
+        hash_errors = HashErrors()
+        for req in chain(root_reqs, discovered_reqs):
+            try:
+                discovered_reqs.extend(self._prepare_file(
+                    finder,
+                    req,
+                    require_hashes=require_hashes,
+                    ignore_dependencies=self.ignore_dependencies))
+            except HashError as exc:
+                exc.req = req
+                hash_errors.append(exc)
+
+        if hash_errors:
+            raise hash_errors
+
+    def _is_upgrade_allowed(self, req):
+        return self.upgrade and (
+            self.upgrade_strategy == "eager" or (
+                self.upgrade_strategy == "only-if-needed" and req.is_direct
+            )
+        )
+
+    def _check_skip_installed(self, req_to_install, finder):
+        """Check if req_to_install should be skipped.
+
+        This will check if the req is installed, and whether we should upgrade
+        or reinstall it, taking into account all the relevant user options.
+
+        After calling this req_to_install will only have satisfied_by set to
+        None if the req_to_install is to be upgraded/reinstalled etc. Any
+        other value will be a dist recording the current thing installed that
+        satisfies the requirement.
+
+        Note that for vcs urls and the like we can't assess skipping in this
+        routine - we simply identify that we need to pull the thing down,
+        then later on it is pulled down and introspected to assess upgrade/
+        reinstalls etc.
+
+        :return: A text reason for why it was skipped, or None.
+        """
+        # Check whether to upgrade/reinstall this req or not.
+        req_to_install.check_if_exists()
+        if req_to_install.satisfied_by:
+            upgrade_allowed = self._is_upgrade_allowed(req_to_install)
+
+            # Is the best version is installed.
+            best_installed = False
+
+            if upgrade_allowed:
+                # For link based requirements we have to pull the
+                # tree down and inspect to assess the version #, so
+                # its handled way down.
+                if not (self.force_reinstall or req_to_install.link):
+                    try:
+                        finder.find_requirement(
+                            req_to_install, upgrade_allowed)
+                    except BestVersionAlreadyInstalled:
+                        best_installed = True
+                    except DistributionNotFound:
+                        # No distribution found, so we squash the
+                        # error - it will be raised later when we
+                        # re-try later to do the install.
+                        # Why don't we just raise here?
+                        pass
+
+                if not best_installed:
+                    # don't uninstall conflict if user install and
+                    # conflict is not user install
+                    if not (self.use_user_site and not
+                            dist_in_usersite(req_to_install.satisfied_by)):
+                        req_to_install.conflicts_with = \
+                            req_to_install.satisfied_by
+                    req_to_install.satisfied_by = None
+
+            # Figure out a nice message to say why we're skipping this.
+            if best_installed:
+                skip_reason = 'already up-to-date'
+            elif self.upgrade_strategy == "only-if-needed":
+                skip_reason = 'not upgraded as not directly required'
+            else:
+                skip_reason = 'already satisfied'
+
+            return skip_reason
+        else:
+            return None
+
+    def _prepare_file(self,
+                      finder,
+                      req_to_install,
+                      require_hashes=False,
+                      ignore_dependencies=False):
+        """Prepare a single requirements file.
+
+        :return: A list of additional InstallRequirements to also install.
+        """
+        # Tell user what we are doing for this requirement:
+        # obtain (editable), skipping, processing (local url), collecting
+        # (remote url or package name)
+        if req_to_install.constraint or req_to_install.prepared:
+            return []
+
+        req_to_install.prepared = True
+
+        # ###################### #
+        # # print log messages # #
+        # ###################### #
+        if req_to_install.editable:
+            logger.info('Obtaining %s', req_to_install)
+        else:
+            # satisfied_by is only evaluated by calling _check_skip_installed,
+            # so it must be None here.
+            assert req_to_install.satisfied_by is None
+            if not self.ignore_installed:
+                skip_reason = self._check_skip_installed(
+                    req_to_install, finder)
+
+            if req_to_install.satisfied_by:
+                assert skip_reason is not None, (
+                    '_check_skip_installed returned None but '
+                    'req_to_install.satisfied_by is set to %r'
+                    % (req_to_install.satisfied_by,))
+                logger.info(
+                    'Requirement %s: %s', skip_reason,
+                    req_to_install)
+            else:
+                if (req_to_install.link and
+                        req_to_install.link.scheme == 'file'):
+                    path = url_to_path(req_to_install.link.url)
+                    logger.info('Processing %s', display_path(path))
+                else:
+                    logger.info('Collecting %s', req_to_install)
+
+        with indent_log():
+            # ################################ #
+            # # vcs update or unpack archive # #
+            # ################################ #
+            if req_to_install.editable:
+                if require_hashes:
+                    raise InstallationError(
+                        'The editable requirement %s cannot be installed when '
+                        'requiring hashes, because there is no single file to '
+                        'hash.' % req_to_install)
+                req_to_install.ensure_has_source_dir(self.src_dir)
+                req_to_install.update_editable(not self.is_download)
+                abstract_dist = make_abstract_dist(req_to_install)
+                abstract_dist.prep_for_dist()
+                if self.is_download:
+                    req_to_install.archive(self.download_dir)
+                req_to_install.check_if_exists()
+            elif req_to_install.satisfied_by:
+                if require_hashes:
+                    logger.debug(
+                        'Since it is already installed, we are trusting this '
+                        'package without checking its hash. To ensure a '
+                        'completely repeatable environment, install into an '
+                        'empty virtualenv.')
+                abstract_dist = Installed(req_to_install)
+            else:
+                # @@ if filesystem packages are not marked
+                # editable in a req, a non deterministic error
+                # occurs when the script attempts to unpack the
+                # build directory
+                req_to_install.ensure_has_source_dir(self.build_dir)
+                # If a checkout exists, it's unwise to keep going.  version
+                # inconsistencies are logged later, but do not fail the
+                # installation.
+                # FIXME: this won't upgrade when there's an existing
+                # package unpacked in `req_to_install.source_dir`
+                if os.path.exists(
+                        os.path.join(req_to_install.source_dir, 'setup.py')):
+                    raise PreviousBuildDirError(
+                        "pip can't proceed with requirements '%s' due to a"
+                        " pre-existing build directory (%s). This is "
+                        "likely due to a previous installation that failed"
+                        ". pip is being responsible and not assuming it "
+                        "can delete this. Please delete it and try again."
+                        % (req_to_install, req_to_install.source_dir)
+                    )
+                req_to_install.populate_link(
+                    finder,
+                    self._is_upgrade_allowed(req_to_install),
+                    require_hashes
+                )
+                # We can't hit this spot and have populate_link return None.
+                # req_to_install.satisfied_by is None here (because we're
+                # guarded) and upgrade has no impact except when satisfied_by
+                # is not None.
+                # Then inside find_requirement existing_applicable -> False
+                # If no new versions are found, DistributionNotFound is raised,
+                # otherwise a result is guaranteed.
+                assert req_to_install.link
+                link = req_to_install.link
+
+                # Now that we have the real link, we can tell what kind of
+                # requirements we have and raise some more informative errors
+                # than otherwise. (For example, we can raise VcsHashUnsupported
+                # for a VCS URL rather than HashMissing.)
+                if require_hashes:
+                    # We could check these first 2 conditions inside
+                    # unpack_url and save repetition of conditions, but then
+                    # we would report less-useful error messages for
+                    # unhashable requirements, complaining that there's no
+                    # hash provided.
+                    if is_vcs_url(link):
+                        raise VcsHashUnsupported()
+                    elif is_file_url(link) and is_dir_url(link):
+                        raise DirectoryUrlHashUnsupported()
+                    if (not req_to_install.original_link and
+                            not req_to_install.is_pinned):
+                        # Unpinned packages are asking for trouble when a new
+                        # version is uploaded. This isn't a security check, but
+                        # it saves users a surprising hash mismatch in the
+                        # future.
+                        #
+                        # file:/// URLs aren't pinnable, so don't complain
+                        # about them not being pinned.
+                        raise HashUnpinned()
+                hashes = req_to_install.hashes(
+                    trust_internet=not require_hashes)
+                if require_hashes and not hashes:
+                    # Known-good hashes are missing for this requirement, so
+                    # shim it with a facade object that will provoke hash
+                    # computation and then raise a HashMissing exception
+                    # showing the user what the hash should be.
+                    hashes = MissingHashes()
+
+                try:
+                    download_dir = self.download_dir
+                    # We always delete unpacked sdists after pip ran.
+                    autodelete_unpacked = True
+                    if req_to_install.link.is_wheel \
+                            and self.wheel_download_dir:
+                        # when doing 'pip wheel` we download wheels to a
+                        # dedicated dir.
+                        download_dir = self.wheel_download_dir
+                    if req_to_install.link.is_wheel:
+                        if download_dir:
+                            # When downloading, we only unpack wheels to get
+                            # metadata.
+                            autodelete_unpacked = True
+                        else:
+                            # When installing a wheel, we use the unpacked
+                            # wheel.
+                            autodelete_unpacked = False
+                    unpack_url(
+                        req_to_install.link, req_to_install.source_dir,
+                        download_dir, autodelete_unpacked,
+                        session=self.session, hashes=hashes)
+                except requests.HTTPError as exc:
+                    logger.critical(
+                        'Could not install requirement %s because '
+                        'of error %s',
+                        req_to_install,
+                        exc,
+                    )
+                    raise InstallationError(
+                        'Could not install requirement %s because '
+                        'of HTTP error %s for URL %s' %
+                        (req_to_install, exc, req_to_install.link)
+                    )
+                abstract_dist = make_abstract_dist(req_to_install)
+                abstract_dist.prep_for_dist()
+                if self.is_download:
+                    # Make a .zip of the source_dir we already created.
+                    if req_to_install.link.scheme in vcs.all_schemes:
+                        req_to_install.archive(self.download_dir)
+                # req_to_install.req is only avail after unpack for URL
+                # pkgs repeat check_if_exists to uninstall-on-upgrade
+                # (#14)
+                if not self.ignore_installed:
+                    req_to_install.check_if_exists()
+                if req_to_install.satisfied_by:
+                    if self.upgrade or self.ignore_installed:
+                        # don't uninstall conflict if user install and
+                        # conflict is not user install
+                        if not (self.use_user_site and not
+                                dist_in_usersite(
+                                    req_to_install.satisfied_by)):
+                            req_to_install.conflicts_with = \
+                                req_to_install.satisfied_by
+                        req_to_install.satisfied_by = None
+                    else:
+                        logger.info(
+                            'Requirement already satisfied (use '
+                            '--upgrade to upgrade): %s',
+                            req_to_install,
+                        )
+
+            # ###################### #
+            # # parse dependencies # #
+            # ###################### #
+            dist = abstract_dist.dist(finder)
+            try:
+                check_dist_requires_python(dist)
+            except UnsupportedPythonVersion as e:
+                if self.ignore_requires_python:
+                    logger.warning(e.args[0])
+                else:
+                    req_to_install.remove_temporary_source()
+                    raise
+            more_reqs = []
+
+            def add_req(subreq, extras_requested):
+                sub_install_req = InstallRequirement(
+                    str(subreq),
+                    req_to_install,
+                    isolated=self.isolated,
+                    wheel_cache=self._wheel_cache,
+                )
+                more_reqs.extend(self.add_requirement(
+                    sub_install_req, req_to_install.name,
+                    extras_requested=extras_requested))
+
+            # We add req_to_install before its dependencies, so that we
+            # can refer to it when adding dependencies.
+            if not self.has_requirement(req_to_install.name):
+                # 'unnamed' requirements will get added here
+                self.add_requirement(req_to_install, None)
+
+            if not ignore_dependencies:
+                if (req_to_install.extras):
+                    logger.debug(
+                        "Installing extra requirements: %r",
+                        ','.join(req_to_install.extras),
+                    )
+                missing_requested = sorted(
+                    set(req_to_install.extras) - set(dist.extras)
+                )
+                for missing in missing_requested:
+                    logger.warning(
+                        '%s does not provide the extra \'%s\'',
+                        dist, missing
+                    )
+
+                available_requested = sorted(
+                    set(dist.extras) & set(req_to_install.extras)
+                )
+                for subreq in dist.requires(available_requested):
+                    add_req(subreq, extras_requested=available_requested)
+
+            # cleanup tmp src
+            self.reqs_to_cleanup.append(req_to_install)
+
+            if not req_to_install.editable and not req_to_install.satisfied_by:
+                # XXX: --no-install leads this to report 'Successfully
+                # downloaded' for only non-editable reqs, even though we took
+                # action on them.
+                self.successfully_downloaded.append(req_to_install)
+
+        return more_reqs
+
+    def cleanup_files(self):
+        """Clean up files, remove builds."""
+        logger.debug('Cleaning up...')
+        with indent_log():
+            for req in self.reqs_to_cleanup:
+                req.remove_temporary_source()
+
+    def _to_install(self):
+        """Create the installation order.
+
+        The installation order is topological - requirements are installed
+        before the requiring thing. We break cycles at an arbitrary point,
+        and make no other guarantees.
+        """
+        # The current implementation, which we may change at any point
+        # installs the user specified things in the order given, except when
+        # dependencies must come earlier to achieve topological order.
+        order = []
+        ordered_reqs = set()
+
+        def schedule(req):
+            if req.satisfied_by or req in ordered_reqs:
+                return
+            if req.constraint:
+                return
+            ordered_reqs.add(req)
+            for dep in self._dependencies[req]:
+                schedule(dep)
+            order.append(req)
+        for install_req in self.requirements.values():
+            schedule(install_req)
+        return order
+
+    def install(self, install_options, global_options=(), *args, **kwargs):
+        """
+        Install everything in this set (after having downloaded and unpacked
+        the packages)
+        """
+        to_install = self._to_install()
+
+        if to_install:
+            logger.info(
+                'Installing collected packages: %s',
+                ', '.join([req.name for req in to_install]),
+            )
+
+        with indent_log():
+            for requirement in to_install:
+                if requirement.conflicts_with:
+                    logger.info(
+                        'Found existing installation: %s',
+                        requirement.conflicts_with,
+                    )
+                    with indent_log():
+                        requirement.uninstall(auto_confirm=True)
+                try:
+                    requirement.install(
+                        install_options,
+                        global_options,
+                        *args,
+                        **kwargs
+                    )
+                except:
+                    # if install did not succeed, rollback previous uninstall
+                    if (requirement.conflicts_with and not
+                            requirement.install_succeeded):
+                        requirement.rollback_uninstall()
+                    raise
+                else:
+                    if (requirement.conflicts_with and
+                            requirement.install_succeeded):
+                        requirement.commit_uninstall()
+                requirement.remove_temporary_source()
+
+        self.successfully_installed = to_install
diff --git a/lib/python2.7/site-packages/pip/req/req_uninstall.py b/lib/python2.7/site-packages/pip/req/req_uninstall.py
new file mode 100644
index 0000000..5248430
--- /dev/null
+++ b/lib/python2.7/site-packages/pip/req/req_uninstall.py
@@ -0,0 +1,195 @@
+from __future__ import absolute_import
+
+import logging
+import os
+import tempfile
+
+from pip.compat import uses_pycache, WINDOWS, cache_from_source
+from pip.exceptions import UninstallationError
+from pip.utils import rmtree, ask, is_local, renames, normalize_path
+from pip.utils.logging import indent_log
+
+
+logger = logging.getLogger(__name__)
+
+
+class UninstallPathSet(object):
+    """A set of file paths to be removed in the uninstallation of a
+    requirement."""
+    def __init__(self, dist):
+        self.paths = set()
+        self._refuse = set()
+        self.pth = {}
+        self.dist = dist
+        self.save_dir = None
+        self._moved_paths = []
+
+    def _permitted(self, path):
+        """
+        Return True if the given path is one we are permitted to
+        remove/modify, False otherwise.
+
+        """
+        return is_local(path)
+
+    def add(self, path):
+        head, tail = os.path.split(path)
+
+        # we normalize the head to resolve parent directory symlinks, but not
+        # the tail, since we only want to uninstall symlinks, not their targets
+        path = os.path.join(normalize_path(head), os.path.normcase(tail))
+
+        if not os.path.exists(path):
+            return
+        if self._permitted(path):
+            self.paths.add(path)
+        else:
+            self._refuse.add(path)
+
+        # __pycache__ files can show up after 'installed-files.txt' is created,
+        # due to imports
+        if os.path.splitext(path)[1] == '.py' and uses_pycache:
+            self.add(cache_from_source(path))
+
+    def add_pth(self, pth_file, entry):
+        pth_file = normalize_path(pth_file)
+        if self._permitted(pth_file):
+            if pth_file not in self.pth:
+                self.pth[pth_file] = UninstallPthEntries(pth_file)
+            self.pth[pth_file].add(entry)
+        else:
+            self._refuse.add(pth_file)
+
+    def compact(self, paths):
+        """Compact a path set to contain the minimal number of paths
+        necessary to contain all paths in the set. If /a/path/ and
+        /a/path/to/a/file.txt are both in the set, leave only the
+        shorter path."""
+        short_paths = set()
+        for path in sorted(paths, key=len):
+            if not any([
+                    (path.startswith(shortpath) and
+                     path[len(shortpath.rstrip(os.path.sep))] == os.path.sep)
+                    for shortpath in short_paths]):
+                short_paths.add(path)
+        return short_paths
+
+    def _stash(self, path):
+        return os.path.join(
+            self.save_dir, os.path.splitdrive(path)[1].lstrip(os.path.sep))
+
+    def remove(self, auto_confirm=False):
+        """Remove paths in ``self.paths`` with confirmation (unless
+        ``auto_confirm`` is True)."""
+        if not self.paths:
+            logger.info(
+                "Can't uninstall '%s'. No files were found to uninstall.",
+                self.dist.project_name,
+            )
+            return
+        logger.info(
+            'Uninstalling %s-%s:',
+            self.dist.project_name, self.dist.version
+        )
+
+        with indent_log():
+            paths = sorted(self.compact(self.paths))
+
+            if auto_confirm:
+                response = 'y'
+            else:
+                for path in paths:
+                    logger.info(path)
+                response = ask('Proceed (y/n)? ', ('y', 'n'))
+            if self._refuse:
+                logger.info('Not removing or modifying (outside of prefix):')
+                for path in self.compact(self._refuse):
+                    logger.info(path)
+            if response == 'y':
+                self.save_dir = tempfile.mkdtemp(suffix='-uninstall',
+                                                 prefix='pip-')
+                for path in paths:
+                    new_path = self._stash(path)
+                    logger.debug('Removing file or directory %s', path)
+                    self._moved_paths.append(path)
+                    renames(path, new_path)
+                for pth in self.pth.values():
+                    pth.remove()
+                logger.info(
+                    'Successfully uninstalled %s-%s',
+                    self.dist.project_name, self.dist.version
+                )
+
+    def rollback(self):
+        """Rollback the changes previously made by remove()."""
+        if self.save_dir is None:
+            logger.error(
+                "Can't roll back %s; was not uninstalled",
+                self.dist.project_name,
+            )
+            return False
+        logger.info('Rolling back uninstall of %s', self.dist.project_name)
+        for path in self._moved_paths:
+            tmp_path = self._stash(path)
+            logger.debug('Replacing %s', path)
+            renames(tmp_path, path)
+        for pth in self.pth.values():
+            pth.rollback()
+
+    def commit(self):
+        """Remove temporary save dir: rollback will no longer be possible."""
+        if self.save_dir is not None:
+            rmtree(self.save_dir)
+            self.save_dir = None
+            self._moved_paths = []
+
+
+class UninstallPthEntries(object):
+    def __init__(self, pth_file):
+        if not os.path.isfile(pth_file):
+            raise UninstallationError(
+                "Cannot remove entries from nonexistent file %s" % pth_file
+            )
+        self.file = pth_file
+        self.entries = set()
+        self._saved_lines = None
+
+    def add(self, entry):
+        entry = os.path.normcase(entry)
+        # On Windows, os.path.normcase converts the entry to use
+        # backslashes.  This is correct for entries that describe absolute
+        # paths outside of site-packages, but all the others use forward
+        # slashes.
+        if WINDOWS and not os.path.splitdrive(entry)[0]:
+            entry = entry.replace('\\', '/')
+        self.entries.add(entry)
+
+    def remove(self):
+        logger.debug('Removing pth entries from %s:', self.file)
+        with open(self.file, 'rb') as fh:
+            # windows uses '\r\n' with py3k, but uses '\n' with py2.x
+            lines = fh.readlines()
+            self._saved_lines = lines
+        if any(b'\r\n' in line for line in lines):
+            endline = '\r\n'
+        else:
+            endline = '\n'
+        for entry in self.entries:
+            try:
+                logger.debug('Removing entry: %s', entry)
+                lines.remove((entry + endline).encode("utf-8"))
+            except ValueError:
+                pass
+        with open(self.file, 'wb') as fh:
+            fh.writelines(lines)
+
+    def rollback(self):
+        if self._saved_lines is None:
+            logger.error(
+                'Cannot roll back changes to %s, none were made', self.file
+            )
+            return False
+        logger.debug('Rolling %s back to previous state', self.file)
+        with open(self.file, 'wb') as fh:
+            fh.writelines(self._saved_lines)
+        return True