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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 rand_student_t(df, mu=0, std=1):
 """ return random number distributed by student's t distribution with `df` degrees of freedom with the specified mean and standard deviation. """


    x = random.gauss(0, std)
    y = 2.0*random.gammavariate(0.5 * df, 2.0)
    return x / (math.sqrt(y / df)) + mu