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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 execute():
 """ Entry point of the install helper tool to ease the download of the right version of the ANTLR v4 tool jar. """


    arg_parser = ArgumentParser(description='Install helper tool to download the right version of the ANTLR v4 tool jar.')

    arg_parser.add_argument('--version', action='version', version='%(prog)s {version}'.format(version=__version__))

    mode_group = arg_parser.add_mutually_exclusive_group()
    mode_group.add_argument('-f', '--force', action='store_true', default=False,
                            help='force download even if local antlr4.jar already exists')
    mode_group.add_argument('-l', '--lazy', action='store_true', default=False,
                            help='don\'t report an error if local antlr4.jar already exists and don\'t try to download it either')

    args = arg_parser.parse_args()

    install(force=args.force, lazy=args.lazy)