code: def test_invalid_tpu_accelerator_count(self):
      with self.assertRaisesRegex(
          ValueError,
          r"Invalid machine configuration",
      ):
          validate.validate(
              entry_point=None,
              distribution_strategy="auto",
              requirements_txt=None,
              chief_config=machine_config.COMMON_MACHINE_CONFIGS["CPU"],
              worker_config=machine_config.MachineConfig(
                  accelerator_type=machine_config.AcceleratorType.TPU_V3
              ),
              worker_count=1,
              entry_point_args=None,
              stream_logs=True,
              docker_image_build_bucket=None,
              called_from_notebook=False,
          )
  
imports: import os
  from absl.testing import absltest
  from tensorflow_cloud.core import machine_config
  from tensorflow_cloud.core import validate
  from tensorflow_cloud.core.tests.unit import constants
label_desc: Use image node_id 18 for calling the TestValidate obj's underlying member method code with example usage: obj.test_invalid_tpu_accelerator_count() without return types