code: def main(args=None, stdin=sys.stdin, stdout=sys.stdout, print_exception=print_exception):
      
      try:
          # Set up logging.
          logging.basicConfig(level=logging.WARN)
  
          kind = args is not None and args[1] or sys.argv[1]
          Runner().run(kind, stdin=stdin, stdout=stdout)
      except Exception as exc:
          # Dump encoded data that we will try to fetch using mechanize
          print_exception(exc)
          raise
docs: Run either the mapper, combiner, or reducer from the class instance in the file "job-instance.pickle".
  
      Arguments:
  
      kind -- is either map, combiner, or reduce