code: def osu_barrier(
      BENCHMARH="MPI Barrier Latency Test",
      skip=1000,
      loop=10000,
      skip_large=10,
      loop_large=100,
      large_message_size=8192,
      MAX_MSG_SIZE=1 << 20,
  ):
      comm = MPI.COMM_WORLD
      myid = comm.Get_rank()
      numprocs = comm.Get_size()
  
      if numprocs < 2:
          if myid == 0:
              errmsg = "This test requires at least two processes"
          else:
              errmsg = None
          raise SystemExit(errmsg)
  
      if myid == 0:
          print(f"# {BENCHMARH}")
      if myid == 0:
          print("# %-8s%20s" % ("Size [B]", "Latency [us]"))
  
      skip = skip_large
      loop = loop_large
      iterations = list(range(loop + skip))
      #
      comm.Barrier()
      for i in iterations:
          if i == skip:
              t_start = MPI.Wtime()
          comm.Barrier()
      t_end = MPI.Wtime()
      comm.Barrier()
      #
      if myid == 0:
          latency = (t_end - t_start) * 1e6 / loop
          print("%-10d%20.2f" % (0, latency))
  
label_desc: Use image node_id 1 for calling a global function with example usage: osu_barrier(BENCHMARH, skip, loop, skip_large, loop_large, large_message_size, MAX_MSG_SIZE) without return types