// _XlaSharding attribute in TF is a serialized string of the OpSharding
      // proto, so convert to a text form here.
      ::xla::OpSharding sharding_proto;
      if (tensorflow::DecodeShardingAttribute(
              op.get_XlaSharding().value().str(), sharding_proto)
              .failed()) {
        return failure();
      }
      // Token is a control signal and not a real data, so arbitrarily assign