def _validate_web_protocol_authn(self, system, credentials):
        system = system.upper()
        if not system in EXTERNAL_MANAGERS:
            raise LoginErrors.LoginError("Invalid system!")

        external_user_id = EXTERNAL_MANAGERS[system].get_user_id(credentials)
        if external_user_id == "":
            raise LoginErrors.InvalidCredentialsError(
                "Invalid username or password!"
            )
        external_user = EXTERNAL_MANAGERS[system].get_user(credentials)
        return external_user_id, external_user
dataset/ETHPy150Open weblabdeusto/weblabdeusto/server/src/weblab/core/login/manager.py/LoginManager._validate_web_protocol_authn/original