mooc在线教育网开发流程总结（三）models

    warning: It seems you set a fixed date / time / datetime value as default for this field. This may not be what you     want. If you want to have the current date as default, use `django.utils.timezone.now`

    出现这种提示，用default=now，非调用now（）来获取current date

多种修改默认user的方法：

继承AbstractUser

    setting里面修改AUTH_USER_MODEL,  from django.contrib.auth.models import AbstractUser

删除多余的django auth表，保留User表扩展的部分