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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 diff_badness(diff):
 """Estimate the "badness" value of a difference map. Returns 0 if the pictures are identical Returns a large number if the pictures are completely different (e.g. a black field and a white field). More specifically, returns ``255 * width * height`` where ``(width, height) == diff.size``. Returns something in between for other situations. """

    # identical pictures = black image = return 0
    # completely different pictures = white image = return lots
    return sum(i * n for i, n in enumerate(diff.histogram()))