code: def test_audio_dataset_from_directory_not_batched(self):
      directory = self._prepare_directory(num_classes=2, count=2)
      dataset = audio_dataset_utils.audio_dataset_from_directory(
          directory,
          batch_size=None,
          output_sequence_length=30,
          label_mode=None,
          shuffle=False,
      )
      sample = next(iter(dataset))
      self.assertEqual(len(sample.shape), 2)
  
imports: import os
  import numpy
  from keras import testing
  from keras.utils import audio_dataset_utils
  from keras.utils.module_utils import tensorflow
label_desc: Use image node_id 16 for calling the AudioDatasetFromDirectoryTest obj's underlying member method code with example usage: obj.test_audio_dataset_from_directory_not_batched() without return types