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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 longest_run_1d(arr):
 """Return the length of the longest consecutive run of identical values. Parameters arr : bool array Input array Returns ------- int Length of longest run. """

    v, rl = rle_1d(arr)[:2]
    return np.where(v, rl, 0).max()