code: def test_image_dataset_from_directory_not_batched(self):
      directory = self._prepare_directory(num_classes=2, count=2)
      dataset = image_dataset_utils.image_dataset_from_directory(
          directory,
          batch_size=None,
          image_size=(18, 18),
          label_mode=None,
          shuffle=False,
      )
      sample = next(iter(dataset))
      self.assertEqual(len(sample.shape), 3)
  
imports: import os
  import numpy
  from keras import backend
  from keras import testing
  from keras.utils import image_dataset_utils
  from keras.utils import image_utils
  from keras.utils.module_utils import tensorflow
label_desc: Use image node_id 15 for calling the ImageDatasetFromDirectoryTest obj's underlying member method code with example usage: obj.test_image_dataset_from_directory_not_batched() without return types