我用的数据库版本太低，不能直接存入json，遂将原来json格式的文件转换成字符串

￥=并用python自带的方法--eval()恢复成原样

例如：将列表里套着的字典类型的做处理

mes = [{'alert_settings': {'sms': '1', 'email': '1'}, 'user_id': '1680700'}, 
{'alert_settings': {'sms': '1', 'email': '1'}, 'user_id': '2857376'}, 
{'alert_settings': {'sms': '1', 'email': '1'}, 'user_id': '2875386'}, 
{'alert_settings': {'sms': '1', 'email': '1'}, 'user_id': '2857422'}, 
{'alert_settings': {'sms': '1', 'email': '1'}, 'user_id': '2881725'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 'user_id': '2891742'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 'user_id': '2998655'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 'user_id': '3265624'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 'user_id': '33638732'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'remind': '1', 'voice': '1', 'push': '1'}, 
'user_id': '3363750'}, {'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 
'user_id': '337923'}, {'alert_settings': {'voice': '1'}, 'user_id': '34833360'}, 
{'alert_settings': {'sms': '1', 'email': '1', 'voice': '1'}, 'user_id': '35545633'}] 

# 将数据转成字符串格式
str_mes = str(mes)