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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 count_init(self):
 """Compute the counts at the first time step Returns ------- n : ndarray(nstates) n[i] is the number of trajectories starting in state i """

        if self.hidden_state_trajectories is None:
            raise RuntimeError('HMM model does not have a hidden state trajectory.')

        n = [traj[0] for traj in self.hidden_state_trajectories]
        return np.bincount(n, minlength=self.nstates)