message: Timeout if TPU initialization doesn't finish in 5 minutes.
diff: @@ -31,6 +31,8 @@ from tensorflow.contrib.tpu.python.tpu import tpu_feed
  from tensorflow.contrib.tpu.python.tpu import tpu_function
  from tensorflow.contrib.tpu.python.tpu import training_loop
  +from tensorflow.core.protobuf import config_pb2
  +
  from tensorflow.python.estimator import estimator as estimator_lib
  from tensorflow.python.estimator import model_fn as model_fn_lib
  from tensorflow.python.estimator import util
  @@ -238,7 +240,8 @@ class TPUInfeedOutfeedSessionHook(session_run_hook.SessionRunHook):
  def after_create_session(self, session, coord):
  logging.info('Init TPU system')
  - session.run(self._init_op)
  + session.run(self._init_op,
  + options=config_pb2.RunOptions(timeout_in_ms=5*60*1000))
  logging.info('Start infeed thread controller')
  self._infeed_thd_controller = _InfeedThreadController(
  