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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 iqr(a):
 """ Calculate the IQR for an array of numbers. """

    a = np.asarray(a)
    q1 = stats.scoreatpercentile(a, 25)
    q3 = stats.scoreatpercentile(a, 75)
    return q3 - q1