code: def main(args=None):
      """Entry-point for ``python -m mpi4py.bench``."""
      # pylint: disable=import-outside-toplevel
      from argparse import ArgumentParser, REMAINDER
  
      parser = ArgumentParser(
          prog=_prog(), usage="%(prog)s [options] <command> [args]"
      )
      parser.add_argument(
          "--threads",
          action="store_true",
          dest="threads",
          default=None,
          help="initialize MPI with thread support",
      )
      parser.add_argument(
          "--no-threads",
          action="store_false",
          dest="threads",
          default=None,
          help="initialize MPI without thread support",
      )
      parser.add_argument(
          "--thread-level",
          dest="thread_level",
          default=None,
          action="store",
          metavar="LEVEL",
          choices="single funneled serialized multiple".split(),
          help="initialize MPI with required thread level",
      )
      parser.add_argument(
          "command",
          action="store",
          metavar="<command>",
          help="benchmark command to run",
      )
      parser.add_argument(
          "args",
          nargs=REMAINDER,
          metavar="[args]",
          help="arguments for benchmark command",
      )
      options = parser.parse_args(args)
  
      from . import rc
  
      if options.threads is not None:
          rc.threads = options.threads
      if options.thread_level is not None:
          rc.thread_level = options.thread_level
  
      from . import MPI
  
      comm = MPI.COMM_WORLD
      if options.command not in main.commands:
          if comm.rank == 0:
              parser.error(f"unknown command {options.command!r}")
          parser.exit(2)
      command = main.commands[options.command]
      command(comm, options.args)
      parser.exit()
  
file_path: mpi4py/src/mpi4py/bench.py
imports: import os
  import sys
label_desc: Use image node_id 7 for calling a global function with example usage: main(args) without return types