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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 is_stationary(self):
 r""" Whether the MSM is stationary, i.e. whether the initial distribution is the stationary distribution of the hidden transition matrix. """

        # for disconnected matrices, the stationary distribution depends on the estimator, so we can't compute
        # it directly. Therefore we test whether the initial distribution is stationary.
        return np.allclose(np.dot(self._Pi, self._Tij), self._Pi)