known = {row['id'] for row in data['manual']}
check('每题均有允许的资料来源', all(row['source_ids'] and set(row['source_ids']) <= known for row in output['questions']))
check('覆盖登记与延期的两份原文', {key for row in output['questions'] for key in row['source_ids']} == known)
save_csv(folder / 'question-bank.csv', output['questions'])
