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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 SampleSum(dists, n):
 """Draws a sample of sums from a list of distributions. dists: sequence of Pmf or Cdf objects n: sample size returns: new Pmf of sums """

    pmf = MakePmfFromList(RandomSum(dists) for i in xrange(n))
    return pmf