TFE_CancellationManager* cancellation_manager) {
  tensorflow::unwrap(cancellation_manager)->StartCancel();
}

bool TFE_CancellationManagerIsCancelled(
    TFE_CancellationManager* cancellation_manager) {
  return tensorflow::unwrap(cancellation_manager)->IsCancelled();
}

bool TFE_CancellationManagerIsCancelling(
    TFE_CancellationManager* cancellation_manager) {

  virtual bool UsesTFRT() = 0;

  // List attributes of available devices
  virtual void ListDevices(std::vector<DeviceAttributes>* devices) = 0;

  // Add `devices` into context's device manager. Context's device manager
  // will take ownership and maintain devices' lifetime.
  virtual Status AddDevices(std::vector<std::unique_ptr<Device>> devices) = 0;

  // Block until all pending nodes are finished.

        ],
        "//conditions:default": [
            ":immediate_execution_context",
            ":immediate_execution_distributed_manager",
            ":immediate_execution_operation",
            ":immediate_execution_tensor_handle",
            ":tfe_cancellation_manager_internal",
            ":tfe_context_internal",
            ":tfe_executor_internal",
            ":tfe_monitoring_internal",

    operation_name_ = operation_name;
    step_id_ = step_id;
    op_inputs_ = inputs;
    attributes_ = attributes;
    expected_max_outputs_ = expected_max_outputs;
    cancellation_manager_ = &cancellation_manager;
    execution_state_ = ExecutionState::kReadyToExecute;
  }
  start_execute_.notify_one();
}

std::vector<TensorHandlePtr> DeviceThread::Join(TF_Status* status) {

    return nullptr;
  }
  return tensor;
}

// Deleter for DLManagedTensor
void DLManagedTensorDeleter(DLManagedTensor* arg) {
  TfDlManagedTensorCtx* owner =
      static_cast<TfDlManagedTensorCtx*>(arg->manager_ctx);
  owner->reference.Unref();
  delete owner;
}

// Converts TF_DATAType to DLPack data type.
DLDataType GetDlDataType(TF_DataType data_type, TF_Status* status) {
  DLDataType dtype;
  dtype.lanes = 1;

// Associates the given `cancellation_manager` with `op`, so that invoking
// `TFE_CancellationManagerStartCancel(cancellation_manager)` will cancel the
// execution of `op`.
typedef struct TFE_CancellationManager TFE_CancellationManager;
TF_CAPI_EXPORT extern void TFE_OpSetCancellationManager(
    TFE_Op* op, TFE_CancellationManager* cancellation_manager,
    TF_Status* status);

  // re-use a thread.
  std::vector<std::unique_ptr<DeviceThread>> device_threads_;
  // A cancellation manager to use if the caller does not provide one. When ops
  // are executed asynchronously this must outlive the queued op, so it can't be
  // function-local to Execute.
  mutable std::unique_ptr<CancellationManager> default_cancellation_manager_;
};

// Contains a tuple of tensors, one on each of the `underlying_devices_` of the

  CancellationManager cancellation_manager;
  parallel_device.StartExecute(context.get(), std::vector<ParallelTensor*>(),
                               "VarHandleOp", TFE_OpGetAttrs(handle_op.get()),
                               /*expected_max_outputs=*/1,
                               cancellation_manager);
  auto outputs = parallel_device.Join(

// Destroy an options object.
TF_CAPI_EXPORT extern void TFE_DeleteContextOptions(TFE_ContextOptions*);

// "Context" under which operations/functions are executed. It encapsulates
// things like the available devices, resource manager etc.
// TFE_Context must outlive all tensor handles created using it. In other
// words, TFE_DeleteContext() must be called after all tensor handles have
// been deleted (with TFE_DeleteTensorHandle).
//

  tensorflow::PluginResource* cc_resource_ptr = new tensorflow::PluginResource(
      plugin_resource, plugin_resource_name, delete_func);
  auto cc_status =
      cc_ctx->resource_manager()->Create<tensorflow::PluginResource>(
          container_name, plugin_resource_name, cc_resource_ptr);
  status->status = cc_status;
}

void TF_LookupOrCreatePluginResource(