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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 _logprior(self):
 """Calculates the log prior at the current parameters."""

        logj = self.logjacobian
        logp = self.prior_distribution(**self.current_params) + logj
        if numpy.isnan(logp):
            logp = -numpy.inf
        return logp