code: def test_invalid_type(self):
      self.N = 10
      self.dataset = ["test"] * self.N
  
      bs = 1
      iterator = chainermn.iterators.create_multi_node_iterator(
          chainer.iterators.SerialIterator(
              self.dataset, batch_size=bs, shuffle=True
          ),
          self.communicator,
      )
  
      with self.assertRaises(TypeError):
          iterator.next()
  
imports: import chainer
  import chainer.testing
  import chainer.testing.attr
  import chainermn
  from chainermn.iterators.multi_node_iterator import _build_ctrl_msg
  from chainermn.iterators.multi_node_iterator import _parse_ctrl_msg
  import numpy
  import platform
  import pytest
  from six.moves import range
  import unittest
label_desc: Use image node_id 2 for calling the TestMultiNodeIteratorDataType obj's underlying member method code with example usage: obj.test_invalid_type() without return types