code: def run(main=None, argv=None):
      
  
      # Define help flags.
      _define_help_flags()
  
      # Parse known flags.
      argv = flags.FLAGS(_sys.argv if argv is None else argv, known_only=True)
  
      main = main or _sys.modules['__main__'].main
  
      # Call the main function, passing through any arguments
      # to the final program.
      _sys.exit(main(argv))
docs: Runs the program with an optional 'main' function and 'argv' list.