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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 rtruncated_pareto(alpha, m, b, size=None):
 """ Random bounded Pareto variates. """

    u = random_number(size)
    return (-(u * b ** alpha - u * m ** alpha - b ** alpha) /
            (b ** alpha * m ** alpha)) ** (-1. / alpha)