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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 pdf(self, mu):
 """ PDF for Poisson prior Parameters mu : float Latent variable for which the prior is being formed over Returns - p(mu) """

        if self.transform is not None:
            mu = self.transform(mu)                
        return ss.poisson.pmf(mu, self.lmd0)