@defer.inlineCallbacks
    def _find_user_id_and_pwd_hash(self, user_id):
        user_infos = yield self.store.get_users_by_id_case_insensitive(user_id)
        if not user_infos:
            logger.warn("Attempted to login as %s but they do not exist", user_id)
            raise LoginError(403, "", errcode=Codes.FORBIDDEN)

        if len(user_infos) > 1:
            if user_id not in user_infos:
                logger.warn(
                    "Attempted to login as %s but it matches more than one user "
                    "inexactly: %r",
                    user_id, user_infos.keys()
                )
                raise LoginError(403, "", errcode=Codes.FORBIDDEN)

            defer.returnValue((user_id, user_infos[user_id]))
        else:
            defer.returnValue(user_infos.popitem())
Start the worker.
dataset/ETHPy150Open matrix-org/synapse/synapse/handlers/auth.py/AuthHandler._find_user_id_and_pwd_hash--crossover with--dataset/ETHPy150Open retresco/Spyder/src/spyder/core/worker.py/ZmqWorker.start