我最近也遇到了同样的错误消息.实际上，这是由于SQLAlchemy的升级，该升级是作为flask-sqlalchemy的依赖项安装的.

I recently delt with that same error message. It is actually due to an upgrade in SQLAlchemy, which gets installed as a dependency of flask-sqlalchemy.

您可以找到我在***上发布的有关该问题的问题

You can find the question I posted on *** for the issue here:

通过卸载SQLAlchemy == 1.4.0并安装先前版本的SQLAlchemy == 1.3.23可以解决此问题.

The problem gets solved by uninstalling SQLAlchemy==1.4.0 and installing the previous version SQLAlchemy==1.3.23.

尝试在虚拟环境中执行此操作，看看是否有帮助.

Try doing that in your virtual environ and see if it helps.