Flask中SQLAlchemy出错：AmbiguousForeignKeysError: Could not determine join condition between parent/child tables on relationship

参考文章：https://www.crifan.com/flask_sqlalchemy_amibiguousforeignkeyserror_could_not_determine_join_condition/

【总结】

当一个表中出现多个：ForeignKey 则SQLAlchemy无法识别，具体哪个属性，从哪个去找，所以报错：
AmbiguousForeignKeysError: Could not determine join condition between parent/child tables on relationship Task.initiator

解决办法：
给db.relationship添加foreign_keys，就可以指明具体是哪个属性了。