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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 MakeMixture(metapmf, name='mix'):
 """Make a mixture distribution. Args: metapmf: Pmf that maps from Pmfs to probs. name: string name for the new Pmf. Returns: Pmf object. """

    mix = Pmf(name=name)
    for pmf, p1 in metapmf.Items():
        for x, p2 in pmf.Items():
            mix.Incr(x, p1 * p2)
    return mix