class User(AbstractUser):
  """
  Users within the Django authentication system are represented by this
  model.

  Username, password and email are required. Other fields are optional.
  """
  class Meta(AbstractUser.Meta):
    swappable = 'AUTH_USER_MODEL'

class User(AbstractUser):
  nickname = models.CharField(max_length=30, blank=True, null=True, verbose_name='昵称')
  qq = models.CharField(max_length=20, blank=True, null=True, verbose_name='QQ号码')
  url = models.URLField(max_length=100, blank=True, null=True, verbose_name='个人网页地址')
  avatar = ProcessedImageField(upload_to='avatar',
default='avatar/default.png', verbose_name='头像')

  class Meta:
    verbose_name = '用户'
    verbose_name_plural = verbose_name
    ordering = ['-id']

  def __str__(self):
    return self.username

ValueError: The field account.EmailAddress.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field admin.LogEntry.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field blog.Article.author was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field easy_comment.Comment.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field easy_comment.Like.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field notifications.Notification.recipient was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field online_status.OnlineStatus.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.
The field socialaccount.SocialAccount.user was declared with a lazy reference to 'blog.user', but app 'blog' doesn't provide model 'user'.

$ python manage.py makemigrations myapp
$ python manage.py migrate

 File "C:\Users\Micky\Anaconda3\lib\site-packages\django\db\backends\utils.py", line 85, in _execute
  return self.cursor.execute(sql, params)
 File "C:\Users\Micky\Anaconda3\lib\site-packages\django\db\backends\sqlite3\base.py", line 303, in execute
  return Database.Cursor.execute(self, query, params)
django.db.utils.OperationalError: no such table: blog_user

#导入AbstractUser类
from django.contrib.auth.models import AbstractUser

#直接继承就可以了，如果有需要就向寻常model一样写字段就可以
class User(AbstractUser):
  pass

#用户名
username = models.CharField(
    _('username'),
    max_length=150,
    unique=True,
    help_text=_('Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only.'),
    validators=[username_validator],
    error_messages={
      'unique': _("A user with that username already exists."),
    },
  )
  
  #名
  first_name = models.CharField(_('first name'), max_length=30, blank=True)
  
  #姓
  last_name = models.CharField(_('last name'), max_length=150, blank=True)
  
  #邮箱
  email = models.EmailField(_('email address'), blank=True)
  
  #权限
  is_staff = models.BooleanField(
    _('staff status'),
    default=False,
    help_text=_('Designates whether the user can log into this admin site.'),
  )
  
  #激活
  is_active = models.BooleanField(
    _('active'),
    default=True,
    help_text=_(
      'Designates whether this user should be treated as active. '
      'Unselect this instead of deleting accounts.'
    ),
  )
  
  #日期
  date_joined = models.DateTimeField(_('date joined'), default=timezone.now)

class LoginView(View):

  def get(self,request):
    #逻辑代码
    return render(request,'login.html')

  def post(self,request):
    # 获取前端传递过来的用户名和密码
    username = request.POST.get('username')
    pwd = request.POST.get('pwd')
    record = request.POST.get('record')
    # 进行数据校验
    if not all([username,pwd]):
      return HttpResponse('数据输入不完整')
    # 验证用户名和密码是否正确
    user = authenticate(username=username,password=pwd)
    return render(request,''index.html')