code: def testValidDataFormatChannelsFirst(self, data_format):
      test = axis_norm.LayerNorm(
          3,
          data_format=data_format,
          create_scale=False,
          create_offset=False,
      )
  
      self.assertEqual(test._channel_index, 1)
  
imports: from absl.testing import parameterized
  import numpy
  from sonnet.src import axis_norm
  from sonnet.src import initializers
  from sonnet.src import test_utils
  import tensorflow
label_desc: Use image node_id 9 for calling the LayerNormTest obj's underlying member method code with example usage: obj.testValidDataFormatChannelsFirst(data_format) without return types