code: def _counter_child():
      parent = MPI.Comm.Get_parent()
      assert parent != MPI.COMM_NULL
      try:
          counter = 0
          status = MPI.Status()
          any_src, any_tag = MPI.ANY_SOURCE, MPI.ANY_TAG
          while True:  # server loop
              incr = parent.recv(None, any_src, any_tag, status)
              if status.tag == 1:
                  break
              parent.send(counter, status.source, 0)
              counter += incr
      finally:
          parent.Disconnect()
  
imports: from mpi4py import MPI
  import sys, os
label_desc: Use image node_id 1 for calling a global function with example usage: _counter_child() without return types