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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 _compute_mle(self):
 """Maximum likelihood estimator. """

        xmax = self._lnlfn.interp.xmax
        x0 = max(self._lnlfn.mle(), xmax * 1e-5)
        ret = opt.fmin(lambda x: np.where(
            xmax > x > 0, -self(x), np.inf), x0, disp=False)
        mle = float(ret[0])
        return mle