来自:兄弟连
查询
User.objects.all()
User.objects.filter(username='zhangsan')
User.objects.exclude(username='zhangsan')
User.objetcs.get(id=1)
User.objetcs.count()
添加
Users.objects.create(**{})
删除
ob.delete()
修改
ob.username = 'aa'
ob.save()