方法一:使用 in 或 not in 来判断。首推该方法。 dict = { 'name': 'Jack', 'age': '21' } 'name' in dict => True 'name' not in dict => False 'id' in dict => False 'id' not in dict => True 'age' not in dict => False 方法二:使用 in dict.keys() 方法来判断,也可以使用 not in dict.keys() dict =
使用SQLAlchemy时报错: sqlalchemy.orm.exc.DetachedInstanceError: Instance <User at 0x809ab1f> is not bound to a Session; attribute refresh operation cannot proceed (Background on this error at: http://sqlalche.me/e/bhk3) 解决方案: 在初始化数据库的代码中,将 maker = sessionmake
Python项目部署后,将新项目添加到/etc/supervisor/conf.d/ 中,然后重新加载: supervisord -c /etc/supervisord.conf 此时会报错: Error: Another program is already listening on a port that one of our HTTP servers is configured to use. Shut this program down first before starting supervi