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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 Marginal(self, i, name=''):
 """Gets the marginal distribution of the indicated variable. i: index of the variable we want Returns: Pmf """

        pmf = Pmf(name=name)
        for vs, prob in self.Items():
            pmf.Incr(vs[i], prob)
        return pmf