polls.UserProfile.user 字段被声明为对“polls.user”的惰性引用，但应用程序“polls”不提供模型“user”

Question

所以我一直在使用这个网站：

https://www.fomfus.com/articles/how-to-use-email-as-username-for-django-authentication-removing-the-username

构建我的项目的一部分，但我不断收到错误

ValueError: The field admin.LogEntry.user was declared with a lazy reference 
to 'polls.user', but app 'polls' doesn't provide model 'user'.
The field calendarium.Event.created_by was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.
The field calendarium.Occurrence.created_by was declared with a lazy 
reference to 'polls.user', but app 'polls' doesn't provide model 'user'.
The field filer.Clipboard.user was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.
The field filer.File.owner was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.
The field filer.Folder.owner was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.
The field filer.FolderPermission.user was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.
The field polls.UserProfile.user was declared with a lazy reference to 
'polls.user', but app 'polls' doesn't provide model 'user'.

我的应用名为 polls，我已确保在我的设置中安装了“polls”，并且

 AUTH_USER_MODEL = 'polls.User'

告诉 Django 这是我要使用的模型。我的models.py也是这样的

from django.contrib.auth.models import AbstractUser, BaseUserManager
from django.db import models
from django.utils.translation import ugettext_lazy as _


    class UserManager(BaseUserManager):
        """Define a model manager for User model with no username field."""

        use_in_migrations = True

        def _create_user(self, email, password, **extra_fields):
            """Create and save a User with the given email and password."""
            if not email:
                raise ValueError('The given email must be set')
            email = self.normalize_email(email)
            user = self.model(email=email, **extra_fields)
            user.set_password(password)
            user.save(using=self._db)
            return user

        def create_user(self, email, password=None, **extra_fields):
            """Create and save a regular User with the given email and 
            password."""
            extra_fields.setdefault('is_staff', False)
            extra_fields.setdefault('is_superuser', False)
            return self._create_user(email, password, **extra_fields)

        def create_superuser(self, email, password, **extra_fields):
            """Create and save a SuperUser with the given email and password."""
            extra_fields.setdefault('is_staff', True)
            extra_fields.setdefault('is_superuser', True)

            if extra_fields.get('is_staff') is not True:
                raise ValueError('Superuser must have is_staff=True.')
            if extra_fields.get('is_superuser') is not True:
                raise ValueError('Superuser must have is_superuser=True.')

            return self._create_user(email, password, **extra_fields)

    class User(AbstractUser):
        """User model."""

        username = None
        email = models.EmailField(_('email address'), unique=True)

        USERNAME_FIELD = 'email'
        REQUIRED_FIELDS = []

        objects = UserManager()

任何人都可以解释为什么会这样吗？并提供解决方案？谢谢

Answer 1

您的应用名称似乎是polls.User，带有大写字母U。但是您在应用calenderium 模型Event 字段created_by 中对该模型的引用是polls.user，带有小写的u。我无法使用您提供的信息重现问题，所以请您尝试解决该问题并回复我吗？