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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 PredictivePmf(self, xs, name=''):
 """Makes a predictive distribution. xs: values to go into the Pmf Returns: Pmf that maps from x to the mean prevalence of x """

        alpha0 = self.params.sum()
        ps = self.params / alpha0
        return MakePmfFromItems(zip(xs, ps), name=name)