Django运行时错误：ContentType模型未声明app_label且不在INSTALLED_APPS中

我的INSTALLED_APPS配置 #

from pathlib import Path
from . import config
import django
django.setup()
import os
BASE_DIR = Path(__file__).resolve().parent.parent

# 安全警告：生产环境请保密密钥！
SECRET_KEY = 'django-insecure-3hs(_o73c=i#c!s(m4yr@c)4k-3=&381r(y6+qy(8b=4p1@l)l'

DEBUG = True

ALLOWED_HOSTS = []

# 应用定义
INSTALLED_APPS = [
'rest_framework_simplejwt',
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'corsheaders',
'users',
'posts',
'settings',
]

运行时错误信息 #

File "/Users/macbook_air/Desktop/ReactRoute/users/models.py", line 2, in 
from django.contrib.auth.models import AbstractUser,Group,Permission
File "/Users/macbook_air/Desktop/ReactRoute/venv/lib/python3.11/site-packages/django/contrib/auth/models.py", line 5, in 
from django.contrib.contenttypes.models import ContentType
File "/Users/macbook_air/Desktop/ReactRoute/venv/lib/python3.11/site-packages/django/contrib/contenttypes/models.py", line 139, in 
class ContentType(models.Model):
File "/Users/macbook_air/Desktop/ReactRoute/venv/lib/python3.11/site-packages/django/db/models/base.py", line 134, in __new__
raise RuntimeError(
RuntimeError: Model class django.contrib.contenttypes.models.ContentType doesn't declare an explicit app_label and isn't in an application in INSTALLED_APPS.

解决步骤 #

1. 删除settings.py中的以下代码：

   import django
   django.setup()
   

2. 保存修改后的settings.py文件
3. 重新启动Django项目

原因说明 #

django.setup()是用于在独立脚本（非Django项目默认启动流程）中初始化Django环境的方法，在settings.py中提前调用会导致Django还未完成配置加载就初始化，进而无法正确识别INSTALLED_APPS中的django.contrib.contenttypes应用，引发上述错误。

内容的提问来源于stack exchange，提问作者Арзбек