code: def test_invalid_batch_no_batch_axis(self):
      args = self.create_batch(
          (
              1,
              3,
          ),
          (1, 3, 1),
      )
      with testing.assert_warns(UserWarning):
          functions.batch_normalization(*args, axis=2)
  
imports: import unittest
  import warnings
  import numpy
  import six
  import chainer
  from chainer.backends import cuda
  from chainer import functions
  from chainer import gradient_check
  from chainer import testing
  from chainer.testing import attr
  from chainer.testing import backend
label_desc: Use image node_id 4 for calling the TestBatchNormalizationWarning obj's underlying member method code with example usage: obj.test_invalid_batch_no_batch_axis() without return types