def items_from_user(self, user_id):
        preferences = self.preferences_from_user(user_id)
        return [key for key, value in preferences]
testing if the login dialog is shown if there is no logged in user
dataset/ETHPy150Open muricoca/crab/scikits/crab/models/classes.py/MatrixPreferenceDataModel.items_from_user--crossover with--dataset/ETHPy150Open eoyilmaz/anima/tests/ui/test_version_creator.py/VersionCreatorTester.test_login_dialog_is_shown_if_there_are_no_logged_in_user