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

        return special.logsumexp(numpy.log(special.i0(mf_snr)),
                                 b=self._deltat) - 0.5*opt_snr