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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 read_stack(stack, plyt=None, laminaprop=None, rho=None, plyts=None, laminaprops=None, rhos=None, offset=0., calc_scf=True):
 """Read a laminate stacking sequence data. An ``Laminate`` object is returned based on the inputs given. Parameters stack : list Angles of the stacking sequence in degrees. plyt : float, optional When all plies have the same thickness, ``plyt`` can be supplied. laminaprop : tuple, optional When all plies have the same material properties, ``laminaprop`` can be supplied. rho : float, optional Uniform material density to be used for all plies. plyts : list, optional A list of floats with the thickness of each ply. laminaprops : list, optional A list of tuples with a laminaprop for each ply. rhos : list, optional A list of floats with the material density of each ply. offset : float, optional Offset along the normal axis about the mid-surface, which influences the laminate properties. calc_scf : bool, optional If True, use :method:`.Laminate.calc_scf` to compute shear correction factors, otherwise the default value of 5/6 is used Notes ----- ``plyt`` or ``plyts`` must be supplied ``laminaprop`` or ``laminaprops`` must be supplied For orthotropic plies, the ``laminaprop`` should be:: laminaprop = (E11, E22, nu12, G12, G13, G23) For isotropic pliey, the ``laminaprop`` should be:: laminaprop = (E, E, nu) """

    lam = Laminate()
    lam.offset = offset
    lam.stack = stack

    if plyts is None:
        if plyt is None:
            raise ValueError('plyt or plyts must be supplied')
        else:
            plyts = [plyt for i in stack]

    if laminaprops is None:
        if laminaprop is None:
            raise ValueError('laminaprop or laminaprops must be supplied')
        else:
            laminaprops = [laminaprop for i in stack]

    if rhos is None:
        rhos = [rho for i in stack]

    lam.plies = []
    for plyt, laminaprop, theta, rho in zip(plyts, laminaprops, stack, rhos):
        laminaprop = laminaprop
        ply = Lamina()
        ply.theta = float(theta)
        ply.h = plyt
        ply.matobj = read_laminaprop(laminaprop, rho)
        lam.plies.append(ply)

    lam.rebuild()
    lam.calc_constitutive_matrix()
    if calc_scf:
        lam.calc_scf()

    return lam