{
 "metadata": {
  "name": ""
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 2: Diffraction of Light"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.1, Page number 2-10"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "theta = 30          #angle(degrees)\n",
      "n = 1        \n",
      "lamda = 6500*10**-8 #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "a = (n*lamda)/math.sin(theta*math.pi/180)\n",
      "\n",
      "#Result\n",
      "print \"a =\",a/1e-4,\"*10^-4 cm\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "a = 1.3 *10^-4 cm\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.2, Page number 2-10"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "a = 6*10**-4        #width of slit(cm)\n",
      "n = 1               #first order\n",
      "lamda = 6000*10**-8 #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "def deg_to_dms(deg):\n",
      "    d = int(deg)\n",
      "    md = abs(deg - d) * 60\n",
      "    m = int(md)\n",
      "    sd = (md - m) * 60\n",
      "    sd=round(sd,2)\n",
      "    return [d, m, sd]\n",
      "\n",
      "theta = (math.asin((n*lamda)/a))*180/math.pi\n",
      "d = 2*theta   #angular seperation\n",
      "\n",
      "#Result\n",
      "print \"Angular seperation between the 1st order minima is\",deg_to_dms(d)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Angular seperation between the 1st order minima is [11, 28, 42.03]\n"
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.3, Page number 2-11"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "n1 = 2       #for second minimum\n",
      "n2 = 3       #for third minimum\n",
      "lamda = 4000 #wavelength(A)\n",
      "\n",
      "#Calculations\n",
      "'''For 2nd order,\n",
      "a sin0 = n1*lamda\n",
      "\n",
      "For 3rd order,\n",
      "a sin0 = n2*lamda'''\n",
      "\n",
      "lamda = (n2*lamda)/n1\n",
      "\n",
      "#Result\n",
      "print \"Wavelength =\",lamda,\"A\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Wavelength = 6000 A\n"
       ]
      }
     ],
     "prompt_number": 11
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.4, Page number 2-11"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "a = 0.16*10**-3      #width of slit(cm)\n",
      "n = 1                #first order\n",
      "lamda = 5600*10**-10 #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "def deg_to_dms(deg):\n",
      "    d = int(deg)\n",
      "    md = abs(deg - d) * 60\n",
      "    m = int(md)\n",
      "    sd = (md - m) * 60\n",
      "    sd=round(sd,2)\n",
      "    return [d, m, sd]\n",
      "\n",
      "theta = (math.asin((n*lamda)/a))*180/math.pi\n",
      "\n",
      "\n",
      "#Result\n",
      "print \"Half angular width=\",deg_to_dms(theta)\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Half angular width= [0, 12, 1.93]\n"
       ]
      }
     ],
     "prompt_number": 22
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.5, Page number 2-11"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "a = 12*10**-5        #width of slit(cm)\n",
      "n = 1                #first order\n",
      "lamda = 6000*10**-8  #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "theta = (math.asin((n*lamda)/a))*180/math.pi\n",
      "\n",
      "\n",
      "#Result\n",
      "print \"Half angular width=\",(theta),\"degrees\"\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Half angular width= 30.0 degrees\n"
       ]
      }
     ],
     "prompt_number": 30
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.2.6, Page number 2-12"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "a = 2*10**-6         #width of slit(cm)\n",
      "n = 1                #first order\n",
      "lamda = 6500*10**-10 #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "theta = (math.asin((n*lamda)/a))*180/math.pi\n",
      "\n",
      "\n",
      "#Result\n",
      "print \"Angle theta =\",round(theta,2),\"degrees\"\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Angle theta = 18.97 degrees\n"
       ]
      }
     ],
     "prompt_number": 34
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.3.1, Page number 2-16"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "a = 0.16  #width(mm)\n",
      "b = 0.8   #distance(mm)\n",
      "\n",
      "#Calculations & Results\n",
      "m = ((a+b)/a)\n",
      "\n",
      "for n in range(1,4):\n",
      "    print \"m =\",m*n\n",
      "    \n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "m = 6.0\n",
        "m = 12.0\n",
        "m = 18.0\n"
       ]
      }
     ],
     "prompt_number": 48
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.1, Page number 2-24"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "lamda1 = 5*10**-5 #cm\n",
      "lamda2 = 7*10**-5 #cm\n",
      "a_plus_b = 1./4000 #cm\n",
      "\n",
      "#Calculations\n",
      "m_max1 = a_plus_b/lamda1\n",
      "m_max2 = round((a_plus_b/lamda2),1)\n",
      "\n",
      "#Results\n",
      "print m_max2,\"orders are visible for 7000 A and\",m_max1,\"orders for 5000 A and either\",m_max2,\",4 or\",m_max1,\"for intermediate wavelengths\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "3.6 orders are visible for 7000 A and 5.0 orders for 5000 A and either 3.6 ,4 or 5.0 for intermediate wavelengths\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.2, Page number 2-24"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "theta = 30   #angle of diffraction(degrees)\n",
      "lamda1 = 5400*10**-8  #cm\n",
      "lamda2 = 4050*10**-8  #cm\n",
      "\n",
      "#Calculations\n",
      "m = lamda2/(lamda1-lamda2)\n",
      "a_plus_b = (m*lamda1)/math.sin(theta*math.pi/180)\n",
      "N = 1/a_plus_b\n",
      "\n",
      "#Result\n",
      "print \"Number of lines per cm =\",round(N,2)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Number of lines per cm = 3086.42\n"
       ]
      }
     ],
     "prompt_number": 60
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.3, Page number 2-25"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "lamda = 4992 #A\n",
      "m1 = 3       #for 3rd order\n",
      "m2 = 4       #for 4th order\n",
      "\n",
      "#Calculations\n",
      "'''For m = 3,\n",
      "(a+b)sin0 = 3*lamda\n",
      "\n",
      "For m = 4,\n",
      "(a+b)sin0 = 4*lamda'''\n",
      "\n",
      "l = (m2*lamda)/m1\n",
      "\n",
      "#Results\n",
      "print \"Wavelength =\",l,\"A\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Wavelength = 6656 A\n"
       ]
      }
     ],
     "prompt_number": 62
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.4, Page number 2-25"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "lamda = 6328*10**-8 #wavelength(cm)\n",
      "m1 = 1\n",
      "m2 = 2\n",
      "a_plus_b = 1./6000  #cm\n",
      "\n",
      "#Calculations\n",
      "theta1 = math.asin((m1*lamda)/a_plus_b)*180/math.pi\n",
      "theta2 = math.asin((m2*lamda)/a_plus_b)*180/math.pi\n",
      "\n",
      "#Result\n",
      "print \"01 =\",round(theta1,2),\"degrees\"\n",
      "print \"02 =\",round(theta2,2),\"degrees\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "01 = 22.31 degrees\n",
        "02 = 49.41 degrees\n"
       ]
      }
     ],
     "prompt_number": 69
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.5, Page number 2-26"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "m = 2              #2nd order\n",
      "lamda = 5*10**-5   #wavelength(cm)\n",
      "theta = 30\n",
      "\n",
      "#Calculations\n",
      "a_plus_b = (m*lamda)/math.sin(theta*math.pi/180)\n",
      "N = 1/a_plus_b\n",
      "\n",
      "#Result\n",
      "print \"The number of lines/cm of the grating surface is\",N"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The number of lines/cm of the grating surface is 5000.0\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.6, Page number 2-26"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "m = 3              #3rd order\n",
      "a_plus_b = 1./7000 #no. of lines/cm\n",
      "sin0 = 1\n",
      "\n",
      "#Calculation\n",
      "lamda = (a_plus_b*sin0)/m\n",
      "\n",
      "#Result\n",
      "print \"Wavelength =\",round(lamda/1e-8),\"A\"\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Wavelength = 4762.0 A\n"
       ]
      }
     ],
     "prompt_number": 7
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.7, Page number 2-26"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "m = 1                 #1st order\n",
      "lamda = 6560*10**-8   #wavelength(cm)\n",
      "theta = 16+12./60\n",
      "\n",
      "#Calculations\n",
      "a_plus_b = (m*lamda)/math.sin(theta*math.pi/180)\n",
      "N = 1/a_plus_b\n",
      "w = 2*N\n",
      "\n",
      "#Result\n",
      "print \"The total number of lines is\",round(w)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The total number of lines is 8506.0\n"
       ]
      }
     ],
     "prompt_number": 15
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.8, Page number 2-27"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "m = 1                 #1st order\n",
      "lamda = 6.56*10**-5   #wavelength(cm)\n",
      "theta = 18+14./60\n",
      "\n",
      "#Calculations\n",
      "a_plus_b = (m*lamda)/math.sin(theta*math.pi/180)\n",
      "N = 1/a_plus_b\n",
      "w = 2*N\n",
      "\n",
      "#Result\n",
      "print \"The total number of lines is\",round(w,1)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The total number of lines is 9539.3\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.9, Page number 2-27"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "lamda = 6*10**-5    #wavelength(cm)\n",
      "a_plus_b = 1./5000  #cm\n",
      "\n",
      "#Calculations\n",
      "m_max = a_plus_b/lamda\n",
      "\n",
      "#Result\n",
      "print \"Order =\",round(m_max)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Order = 3.0\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.10, Page number 2-28"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Variable declaration\n",
      "lamda = 6000*10**-8    #wavelength(cm)\n",
      "a_plus_b = 1./5000     #cm\n",
      "\n",
      "#Calculations\n",
      "m_max = a_plus_b/lamda\n",
      "\n",
      "#Result\n",
      "print \"m_max =\",round(m_max)\n",
      "\n",
      "#The rest of the solution is theoretical"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "m_max = 3.0\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.4.11, Page number 2-28"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Variable declaration\n",
      "m = 1                 #1st order\n",
      "lamda = 5790*10**-8   #wavelength(cm)\n",
      "theta = 19.994\n",
      "\n",
      "#Calculations\n",
      "a_plus_b = (m*lamda)/math.sin(theta*math.pi/180)\n",
      "N = 1/a_plus_b\n",
      "w = 2.54*N\n",
      "\n",
      "#Result\n",
      "print \"The total number of lines is\",round(w)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The total number of lines is 15000.0\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.1, Page number 2-31"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Varaible declaration\n",
      "n = 3000./0.5           #no. of lines per cm\n",
      "m = 2                   #for 2nd order\n",
      "lamda1 = 5893*10**-8    #wavelength(cm)\n",
      "lamda2 = 5896*10**-8    #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "a_plus_b = 1/n\n",
      "theta1 = math.degrees(math.asin((2*lamda1)/(a_plus_b)))\n",
      "theta2 = math.degrees(math.asin((2*lamda2)/(a_plus_b)))\n",
      "d = theta2-theta1       #angular seperation\n",
      "N = lamda1*10**8/(m*3)\n",
      "\n",
      "#Result\n",
      "print \"Since N=\",round(N),\"which is smaller than 3000 lines, the two lines will be resolved in the second order\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Since N= 982.0 which is smaller than 3000 lines, the two lines will be resolved in the second order\n"
       ]
      }
     ],
     "prompt_number": 13
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.2, Page number 2-32"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Varaible declaration\n",
      "m = 3          #for 3rd order\n",
      "lamda = 481    #wavelength(nm)\n",
      "n = 620        #no. of ruling per mm\n",
      "w = 5.05       #width(mm)\n",
      "\n",
      "#Calculations\n",
      "N = n*w\n",
      "dl = lamda/(m*N)\n",
      "\n",
      "#Result\n",
      "print \"Smallest wavelength interval =\",round(dl,4),\"nm\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Smallest wavelength interval = 0.0512 nm\n"
       ]
      }
     ],
     "prompt_number": 15
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.3, Page number 2-33"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "import math\n",
      "\n",
      "#Varaible declaration\n",
      "m = 2          #for 2nd order\n",
      "lamda = 5890   #wavelength(A)\n",
      "dl = 6         #A\n",
      "n = 500.       #no. of lines per cm\n",
      "\n",
      "#Calculations\n",
      "N = lamda/(dl*m)\n",
      "W = N/n\n",
      "\n",
      "#Result\n",
      "print \"Least width =\",W,\"cm\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Least width = 0.98 cm\n"
       ]
      }
     ],
     "prompt_number": 17
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.4, Page number 2-33"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Varaible declaration\n",
      "N = 3*5000               #no. of lines per cm\n",
      "a_plus_b = 1./5000       #cm\n",
      "lamda = 5890*10**-8 #wavelength(cm)\n",
      "\n",
      "#Calculations\n",
      "m_max = round(a_plus_b/lamda)\n",
      "RP = m_max*N\n",
      "\n",
      "#Result\n",
      "print \"Maximum value of resolving power =\",RP"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Maximum value of resolving power = 45000.0\n"
       ]
      }
     ],
     "prompt_number": 24
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.5, Page number 2-34"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Varaible declaration\n",
      "m = 2          #for 2nd order\n",
      "lamda = 5890   #wavelength(A)\n",
      "dl = 6         #A\n",
      "w = 3.         #width of a line(cm)\n",
      "\n",
      "#Calculations\n",
      "lamda2 = lamda+dl\n",
      "N = lamda/(dl*m)\n",
      "\n",
      "a_plus_b = w/N\n",
      "\n",
      "#Results\n",
      "print \"The minimum no. of lines a grating must have is\",N\n",
      "print \"The grating element is\",round(a_plus_b/1e-3,2),\"*10^-3 cm\""
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "The minimum no. of lines a grating must have is 490\n",
        "The grating element is 6.12 *10^-3 cm\n"
       ]
      }
     ],
     "prompt_number": 28
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2.6.6, Page number 2-34"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "#Varaible declaration\n",
      "N = 40000   #no. of lines per cm\n",
      "m = 2       #for 2nd order\n",
      "\n",
      "#Calculations\n",
      "RP = m*N\n",
      "\n",
      "#Result\n",
      "print \"Maximum value of resolving power =\",RP"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Maximum value of resolving power = 80000\n"
       ]
      }
     ],
     "prompt_number": 29
    }
   ],
   "metadata": {}
  }
 ]
}