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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 liftover(args):
 """ %prog liftover gffile > liftover.gff Adjust gff coordinates based on tile number. For example, "gannotation.asmbl.000095.7" is the 8-th tile on asmbl.000095. """

    p = OptionParser(liftover.__doc__)
    p.add_option("--tilesize", default=50000, type="int",
                 help="The size for each tile [default: %default]")
    opts, args = p.parse_args(args)

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

    gffile, = args
    gff = Gff(gffile)
    for g in gff:
        seqid = g.seqid
        seqid, tilenum = seqid.rsplit(".", 1)
        tilenum = int(tilenum)
        g.seqid = seqid
        offset = tilenum * opts.tilesize
        g.start += offset
        g.end += offset
        print(g)