::tensorflow::Status Close() override;

  ::tensorflow::Status ListDevices(
      std::vector<tensorflow::DeviceAttributes>* response) override;

  ::tensorflow::Status LocalDeviceManager(
      const tensorflow::DeviceMgr** deviceMgrPtr) override;

  ::tensorflow::Status Run(
      const std::vector<std::pair<std::string, ::tensorflow::Tensor>>& inputs,

  if (!session || !llvm::hasSingleElement(function)) return success();
  Block& block = function.front();

  const tensorflow::DeviceMgr* mgr = nullptr;
  auto status = session->LocalDeviceManager(&mgr);
  if (!status.ok())
    return function->emitError(
        absl::StrCat("failed to fetch device manager: ", status.message()));

  // Fetch all varHandleOp in the function.

  }

  Status ListDevices(
      std::vector<tensorflow::DeviceAttributes>* response) override {
    return tensorflow::errors::Unimplemented("not available");
  }

  Status LocalDeviceManager(
      const tensorflow::DeviceMgr** deviceMgrPtr) override {
    // This method returns a null device manager without making an error.
    // Users of this method will be notified since it will have a fake data.

}

}  // namespace

LogicalResult InitializeVariablesInSessionInitializer(
    ModuleOp module, tensorflow::Session* session) {
  const tensorflow::DeviceMgr* mgr = nullptr;
  auto status = session->LocalDeviceManager(&mgr);
  if (!status.ok()) {
    module->emitError(
        absl::StrCat("failed to fetch device manager: ", status.message()));
    return failure();
  }

  // Fetch all VarHandleOp.

}

Status FakeSession::ListDevices(
    std::vector<tensorflow::DeviceAttributes>* response) {
  return tensorflow::errors::Unimplemented("not available");
}

Status FakeSession::LocalDeviceManager(
    const tensorflow::DeviceMgr** deviceMgrPtr) {
  Initialize();
  if (kSessionOptions->fail_to_fetch_local_device_manager)
    return Status(absl::StatusCode::kUnknown, "No Local Device Manager");

  if (!status.ok()) {
    return module.emitOpError()
           << "failed to run the provided session: " << status.message();
  }

  const DeviceMgr* device_manager;
  if (!(session->LocalDeviceManager(&device_manager).ok())) {
    return module.emitOpError() << "failed to get local device manager";
  }

  // Read all underlying tensors of the variables from the session.
  std::vector<Tensor> tensors;

LogicalResult FreezeVariables(ModuleOp module, tensorflow::Session* session) {
  if (failed(ValidateModule(module))) return failure();

  const tensorflow::DeviceMgr* mgr = nullptr;
  auto status = session->LocalDeviceManager(&mgr);
  if (!status.ok()) {
    module->emitError(
        absl::StrCat("failed to fetch device manager: ", status.message()));
    return failure();
  }