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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 fll(self, value):
 """ Returns loglike of value """

        self.stochastic.value = value
        try:
            ll = self.loglike
        except ZeroProbability:
            ll = -np.infty
        self.stochastic.revert()
        return ll