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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 group(args):
 """ %prog group anchorfiles Group the anchors into ortho-groups. Can input multiple anchor files. """

    p = OptionParser(group.__doc__)
    p.set_outfile()

    opts, args = p.parse_args(args)

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

    anchorfiles = args
    groups = Grouper()
    for anchorfile in anchorfiles:
        ac = AnchorFile(anchorfile)
        for a, b, idx in ac.iter_pairs():
            groups.join(a, b)

    logging.debug("Created {0} groups with {1} members.".\
                  format(len(groups), groups.num_members))

    outfile = opts.outfile
    fw = must_open(outfile, "w")
    for g in groups:
        print(",".join(sorted(g)), file=fw)
    fw.close()

    return outfile