code: def check_chunked_bcast_obj(self, data_size, max_buf_len):
      root = 0
      obj = np.arange(data_size)
      src = None
      if self.communicator.rank == root:
          src = obj
  
      dst = chunked_bcast_obj(
          src, self.communicator.mpi_comm, max_buf_len, root
      )
      assert len(dst) == len(obj)
      for i in range(len(obj)):
          assert dst[i] == obj[i]
  
file_path: chainer/tests/chainermn_tests/communicator_tests/test_communication_utility.py
imports: import mpi4py
  import numpy
  import pytest
  import unittest
  from chainermn.communicators._communication_utility import chunked_bcast_obj
  from chainermn.communicators._communication_utility import INT_MAX
  from chainermn.communicators.naive_communicator import NaiveCommunicator
label_desc: Use image node_id 3 for calling the TestCommunicationUtility obj's underlying member method code with example usage: obj.check_chunked_bcast_obj(data_size, max_buf_len) without return types