mooc在線教育網開發流程總結（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`

    出現這種提示，用default=now，非調用now（）來獲取current date

多種修改默認user的方法：

繼承AbstractUser

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

刪除多餘的django auth表，保留User表擴展的部分