"""Pythonic way for Dependency Injection - Auth System.""" from dependency_injector import providers from dependency_injector import injections @providers.DelegatedCallable def get_user_info(user_id): """Return user info.""" raise NotImplementedError() @providers.Factory @injections.inject(get_user_info=get_user_info) class AuthComponent(object): """Some authentication component.""" def __init__(self, get_user_info): """Initializer.""" self.get_user_info = get_user_info def authenticate_user(self, token): """Authenticate user by token.""" user_info = self.get_user_info(user_id=token + '1') return user_info print AuthComponent print get_user_info @providers.override(get_user_info) @providers.DelegatedCallable def get_user_info(user_id): """Return user info.""" return {'user_id': user_id} print AuthComponent().authenticate_user(token='abc') # {'user_id': 'abc1'}