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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_Sb(data):
 """ returns vgp scatter for data set """

    Sb, N = 0., 0.
    for rec in data:
        delta = 90. - abs(rec['vgp_lat'])
        if rec['average_k'] != 0:
            k = rec['average_k']
            L = rec['average_lat'] * np.pi / 180.  # latitude in radians
            Nsi = rec['average_nn']
            K = old_div(k, (2. * (1. + 3. * np.sin(L)**2) /
                            (5. - 3. * np.sin(L)**2)))
            Sw = old_div(81., np.sqrt(K))
        else:
            Sw, Nsi = 0, 1.
        Sb += delta**2. - old_div((Sw**2), Nsi)
        N += 1.
    return np.sqrt(old_div(Sb, float(N - 1.)))