def agp(args):
    """
    %prog agp <fastafile|sizesfile>

    Convert the sizes file to a trivial AGP file.
    """
    from jcvi.formats.agp import OO

    p = OptionParser(agp.__doc__)
    opts, args = p.parse_args(args)

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

    sizesfile, = args
    sizes = Sizes(sizesfile)
    agpfile = sizes.filename.rsplit(".", 1)[0] + ".agp"
    fw = open(agpfile, "w")
    o = OO()  # Without a filename
    for ctg, size in sizes.iter_sizes():
        o.add(ctg, ctg, size)

    o.write_AGP(fw)
    fw.close()
    logging.debug("AGP file written to `{0}`.".format(agpfile))

    return agpfile
%prog agp <fastafile|sizesfile>

    Convert the sizes file to a trivial AGP file.