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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 _margtimedist_loglr(self, mf_snr, opt_snr):
 """Returns the log likelihood ratio marginalized over time and distance. """

        logl = special.logsumexp(mf_snr, b=self._deltat)
        logl_marg = logl/self._dist_array
        opt_snr_marg = opt_snr/self._dist_array**2
        return special.logsumexp(logl_marg - 0.5*opt_snr_marg,
                                 b=self._deltad*self.dist_prior)