"""`Singleton` provider example.""" from dependency_injector import containers, providers class UserService: ... class Container(containers.DeclarativeContainer): user_service_provider = providers.Singleton(UserService) if __name__ == "__main__": container = Container() user_service1 = container.user_service_provider() user_service2 = container.user_service_provider() assert user_service1 is user_service2