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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 bounding_box(alpha, threshold=0.1):
 """ Returns a bounding box of the support. Parameters alpha : ndarray, ndim=2 Any one-channel image where the background has zero or low intensity. threshold : float The threshold that divides background from foreground. Returns ------- bounding_box : (top, left, bottom, right) The bounding box describing the smallest rectangle containing the foreground object, as defined by the threshold. """

    assert alpha.ndim == 2

    # Take the bounding box of the support, with a certain threshold.
    supp_axs = [alpha.max(axis=1-i) for i in range(2)]

    # Check first and last value of that threshold
    bb = [np.where(supp_axs[i] > threshold)[0][[0, -1]] for i in range(2)]

    return (bb[0][0], bb[1][0], bb[0][1], bb[1][1])