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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 PorodGuinierPorod(q, a, alpha, Rg, beta):
 """Empirical Porod-Guinier-Porod scattering Inputs: ------- ``q``: independent variable ``a``: factor of the first power-law branch ``alpha``: exponent of the first power-law branch ``Rg``: radius of gyration ``beta``: exponent of the second power-law branch Formula: -------- ``a*q^alpha`` if ``q<q_sep1``. ``G * exp(-q^2*Rg^2/3)`` if ``q_sep1<q<q_sep2`` and ``b*q^beta`` if ``q_sep2<q``. ``q_sep1``, ``q_sep2``, ``G`` and ``b`` are determined from conditions of smoothness at the cross-overs. Literature: B. Hammouda: A new Guinier-Porod model. J. Appl. Crystallogr. (2010) 43, 716-719. """

    return PorodGuinierMulti(q, a, alpha, Rg, beta)