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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 brighten(color, brightness):
 """ Adds or subtracts value to a color. """

    h, s, v = rgb_to_hsv(*map(down_scale, color))
    return tuple(map(up_scale, hsv_to_rgb(h, s, v + down_scale(brightness))))