code: def test_scatter_dataset(self):
      n = self.communicator.size
  
      for shuffle in [True, False]:
          for root in range(self.communicator.size):
              self.check_scatter_dataset([], shuffle, root)
              self.check_scatter_dataset([0], shuffle, root)
              self.check_scatter_dataset(list(range(n)), shuffle, root)
              self.check_scatter_dataset(
                  list(range(n * 5 - 1)), shuffle, root
              )
  
              self.check_scatter_dataset(np.array([]), shuffle, root)
              self.check_scatter_dataset(np.array([0]), shuffle, root)
              self.check_scatter_dataset(np.arange(n), shuffle, root)
              self.check_scatter_dataset(
                  np.arange(n * 5 - 1), shuffle, root
              )
  
              self.check_scatter_dataset(chx.array([]), shuffle, root)
              self.check_scatter_dataset(chx.array([0]), shuffle, root)
              self.check_scatter_dataset(chx.arange(n), shuffle, root)
              self.check_scatter_dataset(
                  chx.arange(n * 5 - 1), shuffle, root
              )
  
imports: from __future__ import with_statement
  import itertools
  import unittest
  import mpi4py.MPI
  import numpy
  import pytest
  from chainer import testing
  import chainermn
  from chainermn.communicators.flat_communicator import FlatCommunicator
  from chainermn.communicators.naive_communicator import NaiveCommunicator
  import chainerx
label_desc: Use image node_id 3 for calling the TestDataset obj's underlying member method code with example usage: obj.test_scatter_dataset() without return types