bool released_ = false;
  F f_;
};

template <int&... ExplicitParameterBarrier, typename F,
          typename DecayF = typename std::decay<F>::type>
Cleanup<DecayF> MakeCleanup(F&& f) {
  return Cleanup<DecayF>(std::forward<F>(f));
}

}  // namespace tf_gcs_filesystem

*   Added experimental support for an exactly-once visitation guarantee for evaluating Keras models trained with `tf.distribute ParameterServerStrategy`, via the `exact_evaluation_shards` argument in `Model.fit` and `Model.evaluate`.