// Runtime. This is necessary to decouple runtime-dependent
  // code that is layered on top of the runtime.
  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 absl::Status AddDevices(

// ListDevices & SessionListDevices API

void TF_DeleteDeviceList(TF_DeviceList* list) { delete list; }

TF_DeviceList* TF_SessionListDevices(TF_Session* session, TF_Status* status) {
  TF_DeviceList* response = new TF_DeviceList;
  if (session && session->session)
    status->status = session->session->ListDevices(&response->response);
  return response;
}

  tensorflow::unwrap(ctx)->Release();
}

TF_DeviceList* TFE_ContextListDevices(TFE_Context* ctx, TF_Status* status) {
  TF_DeviceList* l = new TF_DeviceList;
  tensorflow::unwrap(ctx)->ListDevices(&l->response);
  return l;
}

void TFE_ContextClearCaches(TFE_Context* ctx) {
  tensorflow::unwrap(ctx)->ClearCachesAndThreadExecutors();
}

// Set server_def on the context, possibly updating it.

*   Fix incorrect sampling of small probabilities in CPU/GPU multinomial.
*   Add a list_devices() API on sessions to list devices within a cluster.
    Additionally, this change augment the ListDevices master API to support
    specifying a session.
*   Allow uses of over-parameterized separable convolution.
*   TensorForest multi-regression bug fix.