https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126https://github.com/tensorflow/tpu/issues/1126