docstr: Test loading model with unsupported format.
docstr_tok: ["Test","loading","model","with","unsupported","format","."]
code: def test_load_unsupported_format(self):
      """Test loading model with unsupported format."""
      with self.assertRaisesRegex(
          ValueError, "File format not supported"
      ):
          saving_api.load_model("model.pkl")
  
imports: import os
  import unittest.mock
  import numpy
  from absl import logging
  from keras import layers
  from keras.models import Sequential
  from keras.saving import saving_api
  from keras.testing import test_case
label_desc: Use image node_id 3 for calling the LoadModelTests obj's underlying member method code with example usage: obj.test_load_unsupported_format() without return types