code: def _clean_up():
      for t in _io_threads:
          logger.debug("cleanup thread %s", t)
          t.stop()
      for t in _io_threads:
          logger.debug("join thread %s", t)
          t.join()
  
imports: import logging
  import multiprocessing.connection
  import multiprocessing.reduction
  from multiprocessing.util import register_after_fork
  import atexit
  from fiber.process import current_process
  from fiber.backend import get_backend
  from fiber.socket import Socket, ProcessDevice
label_desc: Use image node_id 1 for calling a global function with example usage: _clean_up() without return types