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

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