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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 _rho02alpha(self, rho0, Rs):
 """ convert rho0 to angle at Rs :param rho0: :param Rs: :return: """


        theta_Rs = rho0 * (4 * Rs ** 2 * (1 + np.log(1. / 2.)))
        return theta_Rs