def METHOD_NAME() -> None:
    args = argparser.parse_args()
    try:
        grammar, parser, tokenizer = build_parser(args.grammar_file)
    except Exception as err:
        print("ERROR: Failed to parse grammar file", file=sys.stderr)
        sys.exit(1)
    firs_sets = FirstSetCalculator(grammar.rules).calculate()
    pprint.pprint(firs_sets)