code: def _sleep():
      while not lp.wait_for_stop(1):
          logging.info("Sleeping again...")
      logging.info("Clean termination of _sleep node")
      time.sleep(2)
  
file_path: launchpad/launchpad/examples/program_wait/launch.py
imports: import threading
  import time
  from absl import app
  from absl import logging
  import launchpad
label_desc: Use image node_id 1 for calling a global function with example usage: _sleep() without return types