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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 logpdf(self, x):
 """ Log PDF for Inverse Gamma prior Parameters x : float Latent variable for which the prior is being formed over Returns - log(p(x)) """

        if self.transform is not None:
            x = self.transform(x)       
        return (-self.alpha-1)*np.log(x) - (self.beta/float(x))