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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_inertia_tensor(elements, coordinates):
 """ Return the tensor of inertia a molecule. Parameters elements : numpy.ndarray The array containing the molecule's elemental data. coordinates : numpy.ndarray The array containing the Cartesian coordinates of the molecule. Returns ------- numpy.ndarray The tensor of inertia of a molecule. """

    pow2 = coordinates**2
    molecular_weight = np.array(
        [[atomic_mass[e.upper()]] for e in elements])

    diag_1 = np.sum(molecular_weight * (pow2[:, 1] + pow2[:, 2]))
    diag_2 = np.sum(molecular_weight * (pow2[:, 0] + pow2[:, 2]))
    diag_3 = np.sum(molecular_weight * (pow2[:, 0] + pow2[:, 1]))

    mxy = np.sum(-molecular_weight * coordinates[:, 0] * coordinates[:, 1])
    mxz = np.sum(-molecular_weight * coordinates[:, 0] * coordinates[:, 2])
    myz = np.sum(-molecular_weight * coordinates[:, 1] * coordinates[:, 2])

    inertia_tensor = np.array([[diag_1, mxy, mxz], [mxy, diag_2, myz],
                               [mxz, myz, diag_3]]) / coordinates.shape[0]
    return (inertia_tensor)