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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_balance_mean(self, ts, t):
 """ Compute the balance. The right end - the left end."""

        """ For changed words we expect an increase in the mean, and so only 1 """
        return np.mean(ts[t + 1:]) - np.mean(ts[:t + 1])