Function get_paginated_answers_requiring_attention_for_exercise 

pub async fn get_paginated_answers_requiring_attention_for_exercise(
    conn: &mut PgConnection,
    exercise_id: Uuid,
    pagination: Pagination,
    viewer_user_id: Uuid,
    fetch_service_info: impl Fn(Url) -> BoxFuture<'static, ModelResult<ExerciseServiceInfoApi>>,
    file_store: &dyn FileStore,
    app_conf: &ApplicationConfiguration,
) -> ModelResult<AnswersRequiringAttention>

Gets submissions that require input from the teacher to continue processing.