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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 Exp(self, m=None):
 """Exponentiates the probabilities. m: how much to shift the ps before exponentiating If m is None, normalizes so that the largest prob is 1. """

        if not self.log:
            raise ValueError("Pmf/Hist not under a log transform")
        self.log = False

        if m is None:
            m = self.MaxLike()

        for x, p in self.d.iteritems():
            self.Set(x, math.exp(p - m))