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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 logpost(self, theta, t=None):
 """Posterior log-density at given parameter values. Parameters theta: dict-like theta['par'] is a ndarray containing the N values for parameter par t: int time (if set to None, the full posterior is returned) Returns ------- l: float numpy.ndarray the N log-likelihood values """

        return self.prior.logpdf(theta) + self.loglik(theta, t)