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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 color(nickname):
 """ Provides a consistent color for a nickname. Uses first 6 chars of nickname's md5 hash, and then slightly darkens the rgb values for use on a light background. """

    _hex = md5(nickname).hexdigest()[:6]
    darken = lambda s: str(int(round(int(s, 16) * .7)))
    return "rgb(%s)" % ",".join([darken(_hex[i:i+2]) for i in range(6)[::2]])