code: def main():
      
      argv = sys.argv[1:]
      returncode = 1
      try:
          returncode = _main(os.environ, argv)
      except exceptions.InvalidArgument as error:
          if error.message:
              sys.stderr.write("Error: " + error.message + '\n')
          else:
              raise
      sys.exit(returncode)
docs: The main command-line entry point, with system interactions.