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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 AvgPool(a, k, strides, padding, data_format):
 """ Average pooling op. """

    if data_format.decode("ascii") == "NCHW":
        a = np.rollaxis(a, 1, -1),

    patches = _pool_patches(a, k, strides, padding.decode("ascii"))
    pool = np.average(patches, axis=tuple(range(-len(k), 0)))

    if data_format.decode("ascii") == "NCHW":
        pool = np.rollaxis(pool, -1, 1)

    return pool,