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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 merge(args):
 """ %prog merge graphs Merge multiple graphs together and visualize. """

    p = OptionParser(merge.__doc__)
    p.add_option("--colorlist", default="black,red,pink,blue,green",
                 help="The color palette [default: %default]")
    opts, args = p.parse_args(args)

    if len(args) < 1:
        sys.exit(not p.print_help())

    colorlist = opts.colorlist.split(",")
    assert len(colorlist) >= len(args), "Need more colors in --colorlist"

    g = BiGraph()
    for a, c in zip(args, colorlist):
        g.read(a, color=c)

    g.draw("merged.png")