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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 jacobian(self, maps):
 """Returns the Jacobian for transforming mchirp and eta to mass1 and mass2. """

        mchirp = maps[parameters.mchirp]
        eta = maps[parameters.eta]
        m1 = conversions.mass1_from_mchirp_eta(mchirp, eta)
        m2 = conversions.mass2_from_mchirp_eta(mchirp, eta)
        return mchirp * (m1 - m2) / (m1 + m2)**3