code: def test_new_group(seed, comm_nccl_opts):
      if comm_nccl_opts is None:
          pytest.skip(
              "Communicator test is disabled. You can turn it on by an option `--test-communicator`."
          )
      try:
          import nnabla_ext
          import nnabla_ext.cuda
      except:
          pytest.skip(
              "{} is supported in CUDA device".format(
                  sys._getframe().f_code.co_name
              )
          )
  
      n_devices = comm_nccl_opts.comm.size
  
      # Reference
      rng = np.random.RandomState(seed)
      device = rng.choice(n_devices)
      groups = {
          "group_i": [device],
          "all": np.arange(n_devices).tolist(),
          "world": np.arange(n_devices).tolist(),
      }
  
      # comm_nccl_opts.comm.new_group
      group_i = comm_nccl_opts.comm.new_group(("group_i", [device]))
      group_all = comm_nccl_opts.comm.new_group(
          ("all", np.arange(n_devices))
      )
  
      # comm_nccl_opts.comm.list_groups
      assert comm_nccl_opts.comm.list_groups() == groups
  
      # comm_nccl_opts.comm.find_group
      assert (
          comm_nccl_opts.comm.find_group("group_i") == groups["group_i"]
      )
      assert comm_nccl_opts.comm.find_group("group_k") == []
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_new_group(seed, comm_nccl_opts) without return types