pub async fn get_course_material_exercise_tasks(
conn: &mut PgConnection,
exercise_slide_id: Uuid,
user_id: Option<Uuid>,
fetch_service_info: impl Fn(Url) -> BoxFuture<'static, ModelResult<ExerciseServiceInfoApi>>,
file_store: &dyn FileStore,
app_conf: &ApplicationConfiguration,
) -> ModelResult<Vec<CourseMaterialExerciseTask>>