Function headless_lms_models::user_course_instance_exercise_service_variables::get_all_variables_for_user_and_course_instance_or_exam

pub(crate) async fn get_all_variables_for_user_and_course_instance_or_exam(
    conn: &mut PgConnection,
    user_id: Uuid,
    instance_or_exam_id: CourseInstanceOrExamId
) -> ModelResult<Vec<UserCourseInstanceExerciseServiceVariable>>