code: def test_save_pretrained_optimizer_state(self):
      model = self.model_init()
      model.build((None, 2))
      save_pretrained_keras(
          model, self.cache_dir, include_optimizer=True
      )
      loaded_model = from_pretrained_keras(self.cache_dir)
      self.assertIsNotNone(loaded_model.optimizer)
  
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 6 for calling the HubKerasSequentialTest obj's underlying member method code with example usage: obj.test_save_pretrained_optimizer_state() without return types