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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 uncertainty_pi(self):
 """Estimate of the element-wise asymptotic standard deviation in the stationary distribution. """

        if self.information_ is None:
            self._build_information()

        sigma_pi = _ratematrix.sigma_pi(
            self.information_, theta=self.theta_, n=self.n_states_)
        return sigma_pi