code: def test_element_spec_shape(self):
      ds = ray.data.from_items(8 * [{"spam": 0, "ham": 0}])
  
      dataset = ds.to_tf(
          feature_columns="spam", label_columns="ham", batch_size=4
      )
  
      feature_spec, label_spec = dataset.element_spec
      assert tuple(feature_spec.shape) == (None,)
      assert tuple(label_spec.shape) == (None,)
  
      features, labels = next(iter(dataset))
      assert tuple(features.shape) == (4,)
      assert tuple(labels.shape) == (4,)
  
file_path: ray/python/ray/data/tests/test_tf.py
imports: import numpy
  import pandas
  import pytest
  import tensorflow
  import ray
  from ray import train
  from ray.data.preprocessors import Concatenator
  from ray.train import ScalingConfig
  from ray.train.tensorflow import TensorflowTrainer
label_desc: Use image node_id 6 for calling the TestToTF obj's underlying member method code with example usage: obj.test_element_spec_shape() without return types