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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 main():
    '''the main entry point for the HelpMe Command line application. Currently,
       the user can request help or set config values for a particular helper.
    '''

    # Customize parser

    parser = get_parser()
    subparsers = get_subparsers(parser)

    def help(return_code=0):
        '''print help, including the software version and active client 
           and exit with return code.
        '''

        version = helpme.__version__
        
        bot.custom(message='Command Line Tool v%s' %version,
                   prefix='\n[HelpMe] ', 
                   color='CYAN')

        parser.print_help()
        sys.exit(return_code)
    
    # If the user didn't provide any arguments, show the full help
    if len(sys.argv) == 1:
        help()
    try:
        args, unknown = parser.parse_known_args()
    except:
        sys.exit(0)

    extras = None
    if args.command in HELPME_HELPERS and len(unknown) > 0:
        extras = unknown

    # if environment logging variable not set, make silent

    if args.debug is False:
        os.environ['MESSAGELEVEL'] = "INFO"

    # Show the version and exit
    if args.version is True:
        print(helpme.__version__)
        sys.exit(0)

    if args.command == "config": from .config import main
    if args.command == "list": from .list import main
    if args.command in HELPME_HELPERS: from .help import main

    # Pass on to the correct parser
    return_code = 0
    try:
        main(args, extras)
        sys.exit(return_code)
    except UnboundLocalError:
        return_code = 1

    help(return_code)