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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 inverse_transform(self, maps):
 """ This function transforms from component masses and cartesian spins to mass-weighted spin parameters aligned with the angular momentum. Parameters maps : a mapping object Returns ------- out : dict A dict with key as parameter name and value as numpy.array or float of transformed values. """

        mass1 = maps[parameters.mass1]
        spin1z = maps[parameters.spin1z]
        mass2 = maps[parameters.mass2]
        spin2z = maps[parameters.spin2z]
        out = {
            parameters.chi_eff : conversions.chi_eff(mass1, mass2,
                                                     spin1z, spin2z),
            "chi_a" : conversions.chi_a(mass1, mass2, spin1z, spin2z),
        }
        return self.format_output(maps, out)