class_docstr: Test suite for classes defined in `transforms` module
class_docstr_tok: ["Test","suite","for","classes","defined","in","`","transforms","`","module"]
code: def test_batch_mulaw(self):
      waveform = common_utils.get_whitenoise(
          sample_rate=8000, duration=1, n_channels=6
      )
      waveform = waveform.reshape(3, 2, -1)
  
      # Single then transform then batch
      expected = [T.MuLawEncoding()(waveform[i]) for i in range(3)]
      expected = torch.stack(expected)
  
      # Batch then transform
      computed = T.MuLawEncoding()(waveform)
  
      # shape = (3, 2, 201, 1394)
      self.assertEqual(computed, expected)
  
      # Single then transform then batch
      expected_decoded = [
          T.MuLawDecoding()(expected[i]) for i in range(3)
      ]
      expected_decoded = torch.stack(expected_decoded)
  
      # Batch then transform
      computed_decoded = T.MuLawDecoding()(computed)
  
      # shape = (3, 2, 201, 1394)
      self.assertEqual(computed_decoded, expected_decoded)
  
imports: import os
  import torch
  from parameterized import parameterized
  from torchaudio import transforms
  from torchaudio_unittest import common_utils
label_desc: Use image node_id 7 for calling the TestTransforms obj's underlying member method code with example usage: obj.test_batch_mulaw() without return types