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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 dlogprior(self, param):
 """Equal to value of `basemodel.dlogprior`."""

        assert param in self.freeparams, "Invalid param: {0}".format(param)
        if param in self.distributionparams:
            return 0.0
        else:
            return self._models[0].dlogprior(param)