def METHOD_NAME(self, svc, db_session, factories):
    user = factories.User()
    annotation = factories.Annotation(userid=user.userid)
    svc.create(user, annotation)
    flag = (
        db_session.query(models.Flag)
        .filter_by(user_id=user.id, annotation_id=annotation.id)
        .first()
    )
    assert flag is not None