Merge pull request #63 from brenda-br/Fix-35HEADmaster

Restructure Project and Deployment

1 files changed, 0 insertions, 971 deletions

diff --git a/venv/Lib/site-packages/pip-19.0.3-py3.7.egg/pip/_internal/download.py b/venv/Lib/site-packages/pip-19.0.3-py3.7.egg/pip/_internal/download.py
deleted file mode 100644
index 2bbe176..0000000
--- a/venv/Lib/site-packages/pip-19.0.3-py3.7.egg/pip/_internal/download.py
+++ /dev/null
@@ -1,971 +0,0 @@
-from __future__ import absolute_import
-
-import cgi
-import email.utils
-import getpass
-import json
-import logging
-import mimetypes
-import os
-import platform
-import re
-import shutil
-import sys
-
-from pip._vendor import requests, six, urllib3
-from pip._vendor.cachecontrol import CacheControlAdapter
-from pip._vendor.cachecontrol.caches import FileCache
-from pip._vendor.lockfile import LockError
-from pip._vendor.requests.adapters import BaseAdapter, HTTPAdapter
-from pip._vendor.requests.auth import AuthBase, HTTPBasicAuth
-from pip._vendor.requests.models import CONTENT_CHUNK_SIZE, Response
-from pip._vendor.requests.structures import CaseInsensitiveDict
-from pip._vendor.requests.utils import get_netrc_auth
-# NOTE: XMLRPC Client is not annotated in typeshed as on 2017-07-17, which is
-#       why we ignore the type on this import
-from pip._vendor.six.moves import xmlrpc_client  # type: ignore
-from pip._vendor.six.moves.urllib import parse as urllib_parse
-from pip._vendor.six.moves.urllib import request as urllib_request
-from pip._vendor.urllib3.util import IS_PYOPENSSL
-
-import pip
-from pip._internal.exceptions import HashMismatch, InstallationError
-from pip._internal.locations import write_delete_marker_file
-from pip._internal.models.index import PyPI
-from pip._internal.utils.encoding import auto_decode
-from pip._internal.utils.filesystem import check_path_owner
-from pip._internal.utils.glibc import libc_ver
-from pip._internal.utils.logging import indent_log
-from pip._internal.utils.misc import (
-    ARCHIVE_EXTENSIONS, ask_path_exists, backup_dir, call_subprocess, consume,
-    display_path, format_size, get_installed_version, rmtree,
-    split_auth_from_netloc, splitext, unpack_file,
-)
-from pip._internal.utils.setuptools_build import SETUPTOOLS_SHIM
-from pip._internal.utils.temp_dir import TempDirectory
-from pip._internal.utils.typing import MYPY_CHECK_RUNNING
-from pip._internal.utils.ui import DownloadProgressProvider
-from pip._internal.vcs import vcs
-
-if MYPY_CHECK_RUNNING:
-    from typing import (  # noqa: F401
-        Optional, Tuple, Dict, IO, Text, Union
-    )
-    from pip._internal.models.link import Link  # noqa: F401
-    from pip._internal.utils.hashes import Hashes  # noqa: F401
-    from pip._internal.vcs import AuthInfo  # noqa: F401
-
-try:
-    import ssl  # noqa
-except ImportError:
-    ssl = None
-
-HAS_TLS = (ssl is not None) or IS_PYOPENSSL
-
-__all__ = ['get_file_content',
-           'is_url', 'url_to_path', 'path_to_url',
-           'is_archive_file', 'unpack_vcs_link',
-           'unpack_file_url', 'is_vcs_url', 'is_file_url',
-           'unpack_http_url', 'unpack_url']
-
-
-logger = logging.getLogger(__name__)
-
-
-def user_agent():
-    """
-    Return a string representing the user agent.
-    """
-    data = {
-        "installer": {"name": "pip", "version": pip.__version__},
-        "python": platform.python_version(),
-        "implementation": {
-            "name": platform.python_implementation(),
-        },
-    }
-
-    if data["implementation"]["name"] == 'CPython':
-        data["implementation"]["version"] = platform.python_version()
-    elif data["implementation"]["name"] == 'PyPy':
-        if sys.pypy_version_info.releaselevel == 'final':
-            pypy_version_info = sys.pypy_version_info[:3]
-        else:
-            pypy_version_info = sys.pypy_version_info
-        data["implementation"]["version"] = ".".join(
-            [str(x) for x in pypy_version_info]
-        )
-    elif data["implementation"]["name"] == 'Jython':
-        # Complete Guess
-        data["implementation"]["version"] = platform.python_version()
-    elif data["implementation"]["name"] == 'IronPython':
-        # Complete Guess
-        data["implementation"]["version"] = platform.python_version()
-
-    if sys.platform.startswith("linux"):
-        from pip._vendor import distro
-        distro_infos = dict(filter(
-            lambda x: x[1],
-            zip(["name", "version", "id"], distro.linux_distribution()),
-        ))
-        libc = dict(filter(
-            lambda x: x[1],
-            zip(["lib", "version"], libc_ver()),
-        ))
-        if libc:
-            distro_infos["libc"] = libc
-        if distro_infos:
-            data["distro"] = distro_infos
-
-    if sys.platform.startswith("darwin") and platform.mac_ver()[0]:
-        data["distro"] = {"name": "macOS", "version": platform.mac_ver()[0]}
-
-    if platform.system():
-        data.setdefault("system", {})["name"] = platform.system()
-
-    if platform.release():
-        data.setdefault("system", {})["release"] = platform.release()
-
-    if platform.machine():
-        data["cpu"] = platform.machine()
-
-    if HAS_TLS:
-        data["openssl_version"] = ssl.OPENSSL_VERSION
-
-    setuptools_version = get_installed_version("setuptools")
-    if setuptools_version is not None:
-        data["setuptools_version"] = setuptools_version
-
-    return "{data[installer][name]}/{data[installer][version]} {json}".format(
-        data=data,
-        json=json.dumps(data, separators=(",", ":"), sort_keys=True),
-    )
-
-
-class MultiDomainBasicAuth(AuthBase):
-
-    def __init__(self, prompting=True):
-        # type: (bool) -> None
-        self.prompting = prompting
-        self.passwords = {}  # type: Dict[str, AuthInfo]
-
-    def __call__(self, req):
-        parsed = urllib_parse.urlparse(req.url)
-
-        # Split the credentials from the netloc.
-        netloc, url_user_password = split_auth_from_netloc(parsed.netloc)
-
-        # Set the url of the request to the url without any credentials
-        req.url = urllib_parse.urlunparse(parsed[:1] + (netloc,) + parsed[2:])
-
-        # Use any stored credentials that we have for this netloc
-        username, password = self.passwords.get(netloc, (None, None))
-
-        # Use the credentials embedded in the url if we have none stored
-        if username is None:
-            username, password = url_user_password
-
-        # Get creds from netrc if we still don't have them
-        if username is None and password is None:
-            netrc_auth = get_netrc_auth(req.url)
-            username, password = netrc_auth if netrc_auth else (None, None)
-
-        if username or password:
-            # Store the username and password
-            self.passwords[netloc] = (username, password)
-
-            # Send the basic auth with this request
-            req = HTTPBasicAuth(username or "", password or "")(req)
-
-        # Attach a hook to handle 401 responses
-        req.register_hook("response", self.handle_401)
-
-        return req
-
-    def handle_401(self, resp, **kwargs):
-        # We only care about 401 responses, anything else we want to just
-        #   pass through the actual response
-        if resp.status_code != 401:
-            return resp
-
-        # We are not able to prompt the user so simply return the response
-        if not self.prompting:
-            return resp
-
-        parsed = urllib_parse.urlparse(resp.url)
-
-        # Prompt the user for a new username and password
-        username = six.moves.input("User for %s: " % parsed.netloc)
-        password = getpass.getpass("Password: ")
-
-        # Store the new username and password to use for future requests
-        if username or password:
-            self.passwords[parsed.netloc] = (username, password)
-
-        # Consume content and release the original connection to allow our new
-        #   request to reuse the same one.
-        resp.content
-        resp.raw.release_conn()
-
-        # Add our new username and password to the request
-        req = HTTPBasicAuth(username or "", password or "")(resp.request)
-        req.register_hook("response", self.warn_on_401)
-
-        # Send our new request
-        new_resp = resp.connection.send(req, **kwargs)
-        new_resp.history.append(resp)
-
-        return new_resp
-
-    def warn_on_401(self, resp, **kwargs):
-        # warn user that they provided incorrect credentials
-        if resp.status_code == 401:
-            logger.warning('401 Error, Credentials not correct for %s',
-                           resp.request.url)
-
-
-class LocalFSAdapter(BaseAdapter):
-
-    def send(self, request, stream=None, timeout=None, verify=None, cert=None,
-             proxies=None):
-        pathname = url_to_path(request.url)
-
-        resp = Response()
-        resp.status_code = 200
-        resp.url = request.url
-
-        try:
-            stats = os.stat(pathname)
-        except OSError as exc:
-            resp.status_code = 404
-            resp.raw = exc
-        else:
-            modified = email.utils.formatdate(stats.st_mtime, usegmt=True)
-            content_type = mimetypes.guess_type(pathname)[0] or "text/plain"
-            resp.headers = CaseInsensitiveDict({
-                "Content-Type": content_type,
-                "Content-Length": stats.st_size,
-                "Last-Modified": modified,
-            })
-
-            resp.raw = open(pathname, "rb")
-            resp.close = resp.raw.close
-
-        return resp
-
-    def close(self):
-        pass
-
-
-class SafeFileCache(FileCache):
-    """
-    A file based cache which is safe to use even when the target directory may
-    not be accessible or writable.
-    """
-
-    def __init__(self, *args, **kwargs):
-        super(SafeFileCache, self).__init__(*args, **kwargs)
-
-        # Check to ensure that the directory containing our cache directory
-        # is owned by the user current executing pip. If it does not exist
-        # we will check the parent directory until we find one that does exist.
-        # If it is not owned by the user executing pip then we will disable
-        # the cache and log a warning.
-        if not check_path_owner(self.directory):
-            logger.warning(
-                "The directory '%s' or its parent directory is not owned by "
-                "the current user and the cache has been disabled. Please "
-                "check the permissions and owner of that directory. If "
-                "executing pip with sudo, you may want sudo's -H flag.",
-                self.directory,
-            )
-
-            # Set our directory to None to disable the Cache
-            self.directory = None
-
-    def get(self, *args, **kwargs):
-        # If we don't have a directory, then the cache should be a no-op.
-        if self.directory is None:
-            return
-
-        try:
-            return super(SafeFileCache, self).get(*args, **kwargs)
-        except (LockError, OSError, IOError):
-            # We intentionally silence this error, if we can't access the cache
-            # then we can just skip caching and process the request as if
-            # caching wasn't enabled.
-            pass
-
-    def set(self, *args, **kwargs):
-        # If we don't have a directory, then the cache should be a no-op.
-        if self.directory is None:
-            return
-
-        try:
-            return super(SafeFileCache, self).set(*args, **kwargs)
-        except (LockError, OSError, IOError):
-            # We intentionally silence this error, if we can't access the cache
-            # then we can just skip caching and process the request as if
-            # caching wasn't enabled.
-            pass
-
-    def delete(self, *args, **kwargs):
-        # If we don't have a directory, then the cache should be a no-op.
-        if self.directory is None:
-            return
-
-        try:
-            return super(SafeFileCache, self).delete(*args, **kwargs)
-        except (LockError, OSError, IOError):
-            # We intentionally silence this error, if we can't access the cache
-            # then we can just skip caching and process the request as if
-            # caching wasn't enabled.
-            pass
-
-
-class InsecureHTTPAdapter(HTTPAdapter):
-
-    def cert_verify(self, conn, url, verify, cert):
-        conn.cert_reqs = 'CERT_NONE'
-        conn.ca_certs = None
-
-
-class PipSession(requests.Session):
-
-    timeout = None  # type: Optional[int]
-
-    def __init__(self, *args, **kwargs):
-        retries = kwargs.pop("retries", 0)
-        cache = kwargs.pop("cache", None)
-        insecure_hosts = kwargs.pop("insecure_hosts", [])
-
-        super(PipSession, self).__init__(*args, **kwargs)
-
-        # Attach our User Agent to the request
-        self.headers["User-Agent"] = user_agent()
-
-        # Attach our Authentication handler to the session
-        self.auth = MultiDomainBasicAuth()
-
-        # Create our urllib3.Retry instance which will allow us to customize
-        # how we handle retries.
-        retries = urllib3.Retry(
-            # Set the total number of retries that a particular request can
-            # have.
-            total=retries,
-
-            # A 503 error from PyPI typically means that the Fastly -> Origin
-            # connection got interrupted in some way. A 503 error in general
-            # is typically considered a transient error so we'll go ahead and
-            # retry it.
-            # A 500 may indicate transient error in Amazon S3
-            # A 520 or 527 - may indicate transient error in CloudFlare
-            status_forcelist=[500, 503, 520, 527],
-
-            # Add a small amount of back off between failed requests in
-            # order to prevent hammering the service.
-            backoff_factor=0.25,
-        )
-
-        # We want to _only_ cache responses on securely fetched origins. We do
-        # this because we can't validate the response of an insecurely fetched
-        # origin, and we don't want someone to be able to poison the cache and
-        # require manual eviction from the cache to fix it.
-        if cache:
-            secure_adapter = CacheControlAdapter(
-                cache=SafeFileCache(cache, use_dir_lock=True),
-                max_retries=retries,
-            )
-        else:
-            secure_adapter = HTTPAdapter(max_retries=retries)
-
-        # Our Insecure HTTPAdapter disables HTTPS validation. It does not
-        # support caching (see above) so we'll use it for all http:// URLs as
-        # well as any https:// host that we've marked as ignoring TLS errors
-        # for.
-        insecure_adapter = InsecureHTTPAdapter(max_retries=retries)
-
-        self.mount("https://", secure_adapter)
-        self.mount("http://", insecure_adapter)
-
-        # Enable file:// urls
-        self.mount("file://", LocalFSAdapter())
-
-        # We want to use a non-validating adapter for any requests which are
-        # deemed insecure.
-        for host in insecure_hosts:
-            self.mount("https://{}/".format(host), insecure_adapter)
-
-    def request(self, method, url, *args, **kwargs):
-        # Allow setting a default timeout on a session
-        kwargs.setdefault("timeout", self.timeout)
-
-        # Dispatch the actual request
-        return super(PipSession, self).request(method, url, *args, **kwargs)
-
-
-def get_file_content(url, comes_from=None, session=None):
-    # type: (str, Optional[str], Optional[PipSession]) -> Tuple[str, Text]
-    """Gets the content of a file; it may be a filename, file: URL, or
-    http: URL.  Returns (location, content).  Content is unicode.
-
-    :param url:         File path or url.
-    :param comes_from:  Origin description of requirements.
-    :param session:     Instance of pip.download.PipSession.
-    """
-    if session is None:
-        raise TypeError(
-            "get_file_content() missing 1 required keyword argument: 'session'"
-        )
-
-    match = _scheme_re.search(url)
-    if match:
-        scheme = match.group(1).lower()
-        if (scheme == 'file' and comes_from and
-                comes_from.startswith('http')):
-            raise InstallationError(
-                'Requirements file %s references URL %s, which is local'
-                % (comes_from, url))
-        if scheme == 'file':
-            path = url.split(':', 1)[1]
-            path = path.replace('\\', '/')
-            match = _url_slash_drive_re.match(path)
-            if match:
-                path = match.group(1) + ':' + path.split('|', 1)[1]
-            path = urllib_parse.unquote(path)
-            if path.startswith('/'):
-                path = '/' + path.lstrip('/')
-            url = path
-        else:
-            # FIXME: catch some errors
-            resp = session.get(url)
-            resp.raise_for_status()
-            return resp.url, resp.text
-    try:
-        with open(url, 'rb') as f:
-            content = auto_decode(f.read())
-    except IOError as exc:
-        raise InstallationError(
-            'Could not open requirements file: %s' % str(exc)
-        )
-    return url, content
-
-
-_scheme_re = re.compile(r'^(http|https|file):', re.I)
-_url_slash_drive_re = re.compile(r'/*([a-z])\|', re.I)
-
-
-def is_url(name):
-    # type: (Union[str, Text]) -> bool
-    """Returns true if the name looks like a URL"""
-    if ':' not in name:
-        return False
-    scheme = name.split(':', 1)[0].lower()
-    return scheme in ['http', 'https', 'file', 'ftp'] + vcs.all_schemes
-
-
-def url_to_path(url):
-    # type: (str) -> str
-    """
-    Convert a file: URL to a path.
-    """
-    assert url.startswith('file:'), (
-        "You can only turn file: urls into filenames (not %r)" % url)
-
-    _, netloc, path, _, _ = urllib_parse.urlsplit(url)
-
-    # if we have a UNC path, prepend UNC share notation
-    if netloc:
-        netloc = '\\\\' + netloc
-
-    path = urllib_request.url2pathname(netloc + path)
-    return path
-
-
-def path_to_url(path):
-    # type: (Union[str, Text]) -> str
-    """
-    Convert a path to a file: URL.  The path will be made absolute and have
-    quoted path parts.
-    """
-    path = os.path.normpath(os.path.abspath(path))
-    url = urllib_parse.urljoin('file:', urllib_request.pathname2url(path))
-    return url
-
-
-def is_archive_file(name):
-    # type: (str) -> bool
-    """Return True if `name` is a considered as an archive file."""
-    ext = splitext(name)[1].lower()
-    if ext in ARCHIVE_EXTENSIONS:
-        return True
-    return False
-
-
-def unpack_vcs_link(link, location):
-    vcs_backend = _get_used_vcs_backend(link)
-    vcs_backend.unpack(location)
-
-
-def _get_used_vcs_backend(link):
-    for backend in vcs.backends:
-        if link.scheme in backend.schemes:
-            vcs_backend = backend(link.url)
-            return vcs_backend
-
-
-def is_vcs_url(link):
-    # type: (Link) -> bool
-    return bool(_get_used_vcs_backend(link))
-
-
-def is_file_url(link):
-    # type: (Link) -> bool
-    return link.url.lower().startswith('file:')
-
-
-def is_dir_url(link):
-    # type: (Link) -> bool
-    """Return whether a file:// Link points to a directory.
-
-    ``link`` must not have any other scheme but file://. Call is_file_url()
-    first.
-
-    """
-    link_path = url_to_path(link.url_without_fragment)
-    return os.path.isdir(link_path)
-
-
-def _progress_indicator(iterable, *args, **kwargs):
-    return iterable
-
-
-def _download_url(
-    resp,  # type: Response
-    link,  # type: Link
-    content_file,  # type: IO
-    hashes,  # type: Hashes
-    progress_bar  # type: str
-):
-    # type: (...) -> None
-    try:
-        total_length = int(resp.headers['content-length'])
-    except (ValueError, KeyError, TypeError):
-        total_length = 0
-
-    cached_resp = getattr(resp, "from_cache", False)
-    if logger.getEffectiveLevel() > logging.INFO:
-        show_progress = False
-    elif cached_resp:
-        show_progress = False
-    elif total_length > (40 * 1000):
-        show_progress = True
-    elif not total_length:
-        show_progress = True
-    else:
-        show_progress = False
-
-    show_url = link.show_url
-
-    def resp_read(chunk_size):
-        try:
-            # Special case for urllib3.
-            for chunk in resp.raw.stream(
-                    chunk_size,
-                    # We use decode_content=False here because we don't
-                    # want urllib3 to mess with the raw bytes we get
-                    # from the server. If we decompress inside of
-                    # urllib3 then we cannot verify the checksum
-                    # because the checksum will be of the compressed
-                    # file. This breakage will only occur if the
-                    # server adds a Content-Encoding header, which
-                    # depends on how the server was configured:
-                    # - Some servers will notice that the file isn't a
-                    #   compressible file and will leave the file alone
-                    #   and with an empty Content-Encoding
-                    # - Some servers will notice that the file is
-                    #   already compressed and will leave the file
-                    #   alone and will add a Content-Encoding: gzip
-                    #   header
-                    # - Some servers won't notice anything at all and
-                    #   will take a file that's already been compressed
-                    #   and compress it again and set the
-                    #   Content-Encoding: gzip header
-                    #
-                    # By setting this not to decode automatically we
-                    # hope to eliminate problems with the second case.
-                    decode_content=False):
-                yield chunk
-        except AttributeError:
-            # Standard file-like object.
-            while True:
-                chunk = resp.raw.read(chunk_size)
-                if not chunk:
-                    break
-                yield chunk
-
-    def written_chunks(chunks):
-        for chunk in chunks:
-            content_file.write(chunk)
-            yield chunk
-
-    progress_indicator = _progress_indicator
-
-    if link.netloc == PyPI.netloc:
-        url = show_url
-    else:
-        url = link.url_without_fragment
-
-    if show_progress:  # We don't show progress on cached responses
-        progress_indicator = DownloadProgressProvider(progress_bar,
-                                                      max=total_length)
-        if total_length:
-            logger.info("Downloading %s (%s)", url, format_size(total_length))
-        else:
-            logger.info("Downloading %s", url)
-    elif cached_resp:
-        logger.info("Using cached %s", url)
-    else:
-        logger.info("Downloading %s", url)
-
-    logger.debug('Downloading from URL %s', link)
-
-    downloaded_chunks = written_chunks(
-        progress_indicator(
-            resp_read(CONTENT_CHUNK_SIZE),
-            CONTENT_CHUNK_SIZE
-        )
-    )
-    if hashes:
-        hashes.check_against_chunks(downloaded_chunks)
-    else:
-        consume(downloaded_chunks)
-
-
-def _copy_file(filename, location, link):
-    copy = True
-    download_location = os.path.join(location, link.filename)
-    if os.path.exists(download_location):
-        response = ask_path_exists(
-            'The file %s exists. (i)gnore, (w)ipe, (b)ackup, (a)abort' %
-            display_path(download_location), ('i', 'w', 'b', 'a'))
-        if response == 'i':
-            copy = False
-        elif response == 'w':
-            logger.warning('Deleting %s', display_path(download_location))
-            os.remove(download_location)
-        elif response == 'b':
-            dest_file = backup_dir(download_location)
-            logger.warning(
-                'Backing up %s to %s',
-                display_path(download_location),
-                display_path(dest_file),
-            )
-            shutil.move(download_location, dest_file)
-        elif response == 'a':
-            sys.exit(-1)
-    if copy:
-        shutil.copy(filename, download_location)
-        logger.info('Saved %s', display_path(download_location))
-
-
-def unpack_http_url(
-    link,  # type: Link
-    location,  # type: str
-    download_dir=None,  # type: Optional[str]
-    session=None,  # type: Optional[PipSession]
-    hashes=None,  # type: Optional[Hashes]
-    progress_bar="on"  # type: str
-):
-    # type: (...) -> None
-    if session is None:
-        raise TypeError(
-            "unpack_http_url() missing 1 required keyword argument: 'session'"
-        )
-
-    with TempDirectory(kind="unpack") as temp_dir:
-        # If a download dir is specified, is the file already downloaded there?
-        already_downloaded_path = None
-        if download_dir:
-            already_downloaded_path = _check_download_dir(link,
-                                                          download_dir,
-                                                          hashes)
-
-        if already_downloaded_path:
-            from_path = already_downloaded_path
-            content_type = mimetypes.guess_type(from_path)[0]
-        else:
-            # let's download to a tmp dir
-            from_path, content_type = _download_http_url(link,
-                                                         session,
-                                                         temp_dir.path,
-                                                         hashes,
-                                                         progress_bar)
-
-        # unpack the archive to the build dir location. even when only
-        # downloading archives, they have to be unpacked to parse dependencies
-        unpack_file(from_path, location, content_type, link)
-
-        # a download dir is specified; let's copy the archive there
-        if download_dir and not already_downloaded_path:
-            _copy_file(from_path, download_dir, link)
-
-        if not already_downloaded_path:
-            os.unlink(from_path)
-
-
-def unpack_file_url(
-    link,  # type: Link
-    location,  # type: str
-    download_dir=None,  # type: Optional[str]
-    hashes=None  # type: Optional[Hashes]
-):
-    # type: (...) -> None
-    """Unpack link into location.
-
-    If download_dir is provided and link points to a file, make a copy
-    of the link file inside download_dir.
-    """
-    link_path = url_to_path(link.url_without_fragment)
-
-    # If it's a url to a local directory
-    if is_dir_url(link):
-        if os.path.isdir(location):
-            rmtree(location)
-        shutil.copytree(link_path, location, symlinks=True)
-        if download_dir:
-            logger.info('Link is a directory, ignoring download_dir')
-        return
-
-    # If --require-hashes is off, `hashes` is either empty, the
-    # link's embedded hash, or MissingHashes; it is required to
-    # match. If --require-hashes is on, we are satisfied by any
-    # hash in `hashes` matching: a URL-based or an option-based
-    # one; no internet-sourced hash will be in `hashes`.
-    if hashes:
-        hashes.check_against_path(link_path)
-
-    # If a download dir is specified, is the file already there and valid?
-    already_downloaded_path = None
-    if download_dir:
-        already_downloaded_path = _check_download_dir(link,
-                                                      download_dir,
-                                                      hashes)
-
-    if already_downloaded_path:
-        from_path = already_downloaded_path
-    else:
-        from_path = link_path
-
-    content_type = mimetypes.guess_type(from_path)[0]
-
-    # unpack the archive to the build dir location. even when only downloading
-    # archives, they have to be unpacked to parse dependencies
-    unpack_file(from_path, location, content_type, link)
-
-    # a download dir is specified and not already downloaded
-    if download_dir and not already_downloaded_path:
-        _copy_file(from_path, download_dir, link)
-
-
-def _copy_dist_from_dir(link_path, location):
-    """Copy distribution files in `link_path` to `location`.
-
-    Invoked when user requests to install a local directory. E.g.:
-
-        pip install .
-        pip install ~/dev/git-repos/python-prompt-toolkit
-
-    """
-
-    # Note: This is currently VERY SLOW if you have a lot of data in the
-    # directory, because it copies everything with `shutil.copytree`.
-    # What it should really do is build an sdist and install that.
-    # See https://github.com/pypa/pip/issues/2195
-
-    if os.path.isdir(location):
-        rmtree(location)
-
-    # build an sdist
-    setup_py = 'setup.py'
-    sdist_args = [sys.executable]
-    sdist_args.append('-c')
-    sdist_args.append(SETUPTOOLS_SHIM % setup_py)
-    sdist_args.append('sdist')
-    sdist_args += ['--dist-dir', location]
-    logger.info('Running setup.py sdist for %s', link_path)
-
-    with indent_log():
-        call_subprocess(sdist_args, cwd=link_path, show_stdout=False)
-
-    # unpack sdist into `location`
-    sdist = os.path.join(location, os.listdir(location)[0])
-    logger.info('Unpacking sdist %s into %s', sdist, location)
-    unpack_file(sdist, location, content_type=None, link=None)
-
-
-class PipXmlrpcTransport(xmlrpc_client.Transport):
-    """Provide a `xmlrpclib.Transport` implementation via a `PipSession`
-    object.
-    """
-
-    def __init__(self, index_url, session, use_datetime=False):
-        xmlrpc_client.Transport.__init__(self, use_datetime)
-        index_parts = urllib_parse.urlparse(index_url)
-        self._scheme = index_parts.scheme
-        self._session = session
-
-    def request(self, host, handler, request_body, verbose=False):
-        parts = (self._scheme, host, handler, None, None, None)
-        url = urllib_parse.urlunparse(parts)
-        try:
-            headers = {'Content-Type': 'text/xml'}
-            response = self._session.post(url, data=request_body,
-                                          headers=headers, stream=True)
-            response.raise_for_status()
-            self.verbose = verbose
-            return self.parse_response(response.raw)
-        except requests.HTTPError as exc:
-            logger.critical(
-                "HTTP error %s while getting %s",
-                exc.response.status_code, url,
-            )
-            raise
-
-
-def unpack_url(
-    link,  # type: Optional[Link]
-    location,  # type: Optional[str]
-    download_dir=None,  # type: Optional[str]
-    only_download=False,  # type: bool
-    session=None,  # type: Optional[PipSession]
-    hashes=None,  # type: Optional[Hashes]
-    progress_bar="on"  # type: str
-):
-    # type: (...) -> None
-    """Unpack link.
-       If link is a VCS link:
-         if only_download, export into download_dir and ignore location
-          else unpack into location
-       for other types of link:
-         - unpack into location
-         - if download_dir, copy the file into download_dir
-         - if only_download, mark location for deletion
-
-    :param hashes: A Hashes object, one of whose embedded hashes must match,
-        or HashMismatch will be raised. If the Hashes is empty, no matches are
-        required, and unhashable types of requirements (like VCS ones, which
-        would ordinarily raise HashUnsupported) are allowed.
-    """
-    # non-editable vcs urls
-    if is_vcs_url(link):
-        unpack_vcs_link(link, location)
-
-    # file urls
-    elif is_file_url(link):
-        unpack_file_url(link, location, download_dir, hashes=hashes)
-
-    # http urls
-    else:
-        if session is None:
-            session = PipSession()
-
-        unpack_http_url(
-            link,
-            location,
-            download_dir,
-            session,
-            hashes=hashes,
-            progress_bar=progress_bar
-        )
-    if only_download:
-        write_delete_marker_file(location)
-
-
-def _download_http_url(
-    link,  # type: Link
-    session,  # type: PipSession
-    temp_dir,  # type: str
-    hashes,  # type: Hashes
-    progress_bar  # type: str
-):
-    # type: (...) -> Tuple[str, str]
-    """Download link url into temp_dir using provided session"""
-    target_url = link.url.split('#', 1)[0]
-    try:
-        resp = session.get(
-            target_url,
-            # We use Accept-Encoding: identity here because requests
-            # defaults to accepting compressed responses. This breaks in
-            # a variety of ways depending on how the server is configured.
-            # - Some servers will notice that the file isn't a compressible
-            #   file and will leave the file alone and with an empty
-            #   Content-Encoding
-            # - Some servers will notice that the file is already
-            #   compressed and will leave the file alone and will add a
-            #   Content-Encoding: gzip header
-            # - Some servers won't notice anything at all and will take
-            #   a file that's already been compressed and compress it again
-            #   and set the Content-Encoding: gzip header
-            # By setting this to request only the identity encoding We're
-            # hoping to eliminate the third case. Hopefully there does not
-            # exist a server which when given a file will notice it is
-            # already compressed and that you're not asking for a
-            # compressed file and will then decompress it before sending
-            # because if that's the case I don't think it'll ever be
-            # possible to make this work.
-            headers={"Accept-Encoding": "identity"},
-            stream=True,
-        )
-        resp.raise_for_status()
-    except requests.HTTPError as exc:
-        logger.critical(
-            "HTTP error %s while getting %s", exc.response.status_code, link,
-        )
-        raise
-
-    content_type = resp.headers.get('content-type', '')
-    filename = link.filename  # fallback
-    # Have a look at the Content-Disposition header for a better guess
-    content_disposition = resp.headers.get('content-disposition')
-    if content_disposition:
-        type, params = cgi.parse_header(content_disposition)
-        # We use ``or`` here because we don't want to use an "empty" value
-        # from the filename param.
-        filename = params.get('filename') or filename
-    ext = splitext(filename)[1]
-    if not ext:
-        ext = mimetypes.guess_extension(content_type)
-        if ext:
-            filename += ext
-    if not ext and link.url != resp.url:
-        ext = os.path.splitext(resp.url)[1]
-        if ext:
-            filename += ext
-    file_path = os.path.join(temp_dir, filename)
-    with open(file_path, 'wb') as content_file:
-        _download_url(resp, link, content_file, hashes, progress_bar)
-    return file_path, content_type
-
-
-def _check_download_dir(link, download_dir, hashes):
-    # type: (Link, str, Hashes) -> Optional[str]
-    """ Check download_dir for previously downloaded file with correct hash
-        If a correct file is found return its path else None
-    """
-    download_path = os.path.join(download_dir, link.filename)
-    if os.path.exists(download_path):
-        # If already downloaded, does its hash match?
-        logger.info('File was already downloaded %s', download_path)
-        if hashes:
-            try:
-                hashes.check_against_path(download_path)
-            except HashMismatch:
-                logger.warning(
-                    'Previously-downloaded file %s has bad hash. '
-                    'Re-downloading.',
-                    download_path
-                )
-                os.unlink(download_path)
-                return None
-        return download_path
-    return None