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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 GuinierPorodGuinier(q, G, Rg1, alpha, Rg2):
 """Empirical Guinier-Porod-Guinier scattering Inputs: ------- ``q``: independent variable ``G``: factor for the first Guinier-branch ``Rg1``: the first radius of gyration ``alpha``: the power-law exponent ``Rg2``: the second radius of gyration Formula: -------- ``G*exp(-q^2*Rg1^2/3)`` if ``q<q_sep1``. ``A*q^alpha`` if ``q_sep1 <= q <=q_sep2``. ``G2*exp(-q^2*Rg2^2/3)`` if ``q_sep2<q``. The parameters ``A``,``G2``, ``q_sep1``, ``q_sep2`` 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 GuinierPorodMulti(q, G, Rg1, alpha, Rg2)