code: def require_tf(test_case):
      """
      Decorator marking a test that requires TensorFlow, graphviz and pydot.
  
      These tests are skipped when TensorFlow, graphviz and pydot are installed.
  
      """
      if (
          not is_tf_available()
          or not is_pydot_available()
          or not is_graphviz_available()
      ):
          return unittest.skip(
              "test requires Tensorflow, graphviz and pydot."
          )(test_case)
      else:
          return test_case
  
imports: import json
  import os
  import unittest
  from pathlib import Path
  import pytest
  from huggingface_hub import HfApi, hf_hub_download, snapshot_download
  from huggingface_hub.keras_mixin import KerasModelHubMixin, from_pretrained_keras, push_to_hub_keras, save_pretrained_keras
  from huggingface_hub.utils import is_graphviz_available, is_pydot_available, is_tf_available, logging
  from .testing_constants import ENDPOINT_STAGING, TOKEN, USER
  from .testing_utils import repo_name
label_desc: Use image node_id 1 for calling a global function with example usage: require_tf(test_case) and returns: unittest, test_case