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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 counter_clockwise(cx, cy):
 """Put contour coordinates into counter-clockwise order Parameters cx, cy: 1d ndarrays The x- and y-coordinates of the contour Returns ------- cx_cc, cy_cc: The x- and y-coordinates of the contour in counter-clockwise orientation. """

    # test orientation
    angles = np.unwrap(np.arctan2(cy, cx))
    grad = np.gradient(angles)
    if np.average(grad) > 0:
        return cx[::-1], cy[::-1]
    else:
        return cx, cy