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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 CredibleInterval(pmf, percentage=90):
 """Computes a credible interval for a given distribution. If percentage=90, computes the 90% CI. Args: pmf: Pmf object representing a posterior distribution percentage: float between 0 and 100 Returns: sequence of two floats, low and high """

    cdf = pmf.MakeCdf()
    prob = (1 - percentage / 100.0) / 2
    interval = cdf.Value(prob), cdf.Value(1 - prob)
    return interval