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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 rgb2ansi(r, g, b):
 """ Convert an RGB color to 256 ansi graphics. """


    # Thanks to
    # https://github.com/tehmaze/ansi/blob/master/ansi/colour/rgb.py

    grayscale = False
    poss = True
    step = 2.5

    while poss:
        if min(r, g, b) < step:
            grayscale = max(r, g, b) < step
            poss = False

        step += 42.5

    if grayscale:
        return 232 + int(float(sum((r, g, b)) / 33.0))

    m = ((r, 36), (g, 6), (b, 1))
    return 16 + sum(int(6 * float(val) / 256) * mod for val, mod in m)