def replied(self):
        if self.replied_at is not None:
            return True
        return False
A convenience method that turns a query into an EXISTS subquery
dataset/ETHPy150Open amarandon/smeuhsocial/apps/messages/models.py/Message.replied--crossover with--dataset/ETHPy150Open goFrendiAsgard/kokoropy/kokoropy/packages/sqlalchemy/orm/query.py/Query.exists