"""`Dependency` provider undefined error example.""" import abc import dataclasses from dependency_injector import containers, providers class DbAdapter(metaclass=abc.ABCMeta): ... @dataclasses.dataclass class UserService: database: DbAdapter class Container(containers.DeclarativeContainer): database = providers.Dependency(instance_of=DbAdapter) user_service = providers.Factory( UserService, database=database, ) if __name__ == "__main__": container = Container() container.user_service() # <-- raises error: # Dependency "Container.database" is not defined