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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 stationary_distribution(self):
 r""" Compute stationary distribution of hidden states if possible. Raises ------ ValueError if the HMM is not stationary """

        assert _tmatrix_disconnected.is_connected(self._Tij, strong=False), \
            'No unique stationary distribution because transition matrix is not connected'
        import msmtools.analysis as msmana
        return msmana.stationary_distribution(self._Tij)