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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 add_options(p, args, dist=10):
 """ scan and liftover has similar interfaces, so share common options returns opts, files """

    p.set_beds()
    p.add_option("--dist", default=dist, type="int",
            help="Extent of flanking regions to search [default: %default]")

    opts, args = p.parse_args(args)

    if len(args) != 2:
        sys.exit(not p.print_help())

    blast_file, anchor_file = args

    return blast_file, anchor_file, opts.dist, opts