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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 integrate(ii, r0, c0, r1, c1):
 """ Use an integral image to integrate over a given window. Parameters ii : ndarray Integral image. r0, c0 : int Top-left corner of block to be summed. r1, c1 : int Bottom-right corner of block to be summed. Returns ------- S : int Integral (sum) over the given window. """

    # This line is modified
    S = np.zeros(ii.shape[-1])

    S += ii[r1, c1]

    if (r0 - 1 >= 0) and (c0 - 1 >= 0):
        S += ii[r0 - 1, c0 - 1]

    if (r0 - 1 >= 0):
        S -= ii[r0 - 1, c1]

    if (c0 - 1 >= 0):
        S -= ii[r1, c0 - 1]

    return S