code: def testNumAcceleratorsRetryFailure(
      self, mock_list_devices, mock_eager_list_devices
  ):
      tpu_map = {
          "projects/test-project/locations/us-central1-c/nodes/test-tpu-1": {
              "health": "HEALTHY",
              "networkEndpoints": [
                  {
                      "ipAddress": "10.2.3.4",
                      "port": 8470,
                  },
                  {
                      "ipAddress": "10.2.3.5",
                      "port": 8470,
                  },
                  {
                      "ipAddress": "10.2.3.6",
                      "port": 8470,
                  },
                  {
                      "ipAddress": "10.2.3.7",
                      "port": 8470,
                  },
              ],
          }
      }
  
      cluster_resolver = resolver.TPUClusterResolver(
          project="test-project",
          zone="us-central1-c",
          tpu="test-tpu-1",
          service=self.mock_service_client(tpu_map=tpu_map),
      )
      mock_list_devices.side_effect = errors.DeadlineExceededError(
          None, None, "timeout"
      )
      mock_eager_list_devices.side_effect = (
          errors.DeadlineExceededError(None, None, "timeout")
      )
      with self.assertRaises(RuntimeError):
          cluster_resolver.num_accelerators()
  
imports: import os
  import six
  from six.moves.urllib.error import URLError
  from tensorflow.core.protobuf.tpu import topology_pb2
  from tensorflow.python.client import session
  from tensorflow.python.distribute.cluster_resolver.tpu import tpu_cluster_resolver
  from tensorflow.python.eager import context
  from tensorflow.python.framework import config
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import test_util
  from tensorflow.python.platform import test
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.training import server_lib
  from tensorflow.python.util import compat
label_desc: Use image node_id 28 for calling the TPUClusterResolverTest obj's underlying member method code with example usage: obj.testNumAcceleratorsRetryFailure(mock_list_devices, mock_eager_list_devices) without return types