Python 无法执行makemigrations命令

我将在发生此错误之前向大家介绍我所做的步骤

Traceback (most recent call last):
  File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py", line 155, in get_app_config
    return self.app_configs[app_label]
KeyError: 'admin'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 17, in main
    execute_from_command_line(sys.argv)
  File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 395, in execute self.fetch_command(subcommand).run_from_argv(self.argv)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 328, in run_from_argv
    self.execute(*args, **cmd_options)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 366, in execute
    self.check()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 392, in check
    all_issues = self._run_checks(

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 382, in _run_checks
    return checks.run_checks(**kwargs)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
    new_errors = check(app_configs=app_configs)

 File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py", line 13, in check_url_config
    return check_resolver(resolver)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py", line 23, in check_resolver
    return check_method()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 407, in check
    for pattern in self.url_patterns:

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 588, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 581, in urlconf_module
    return import_module(self.urlconf_name)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)

File "<frozen importlib._bootstrap>", line 1014, in _gcd_import

File "<frozen importlib._bootstrap>", line 991, in _find_and_load

File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked

File "<frozen importlib._bootstrap>", line 671, in _load_unlocked

 File "<frozen importlib._bootstrap_external>", line 783, in exec_module

File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed

File "C:\myproj\myproj\urls.py", line 20, in <module>
    path('admin/', admin.site.urls),

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 224, in inner
    self._setup()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\contrib\admin\sites.py", line 537, in _setup
    AdminSiteClass = import_string(apps.get_app_config('admin').default_site)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py", line 162, in get_app_config
    raise LookupError(message)

LookupError: No installed app with label 'admin'.

顺便说一句，我的超级用户=>id:myuser电子邮件：pass:myuser

    hostname $ django-admin.py startproject myproj

    hostname $ cd myproj

    hostname $ python manage.py startapp myapp

    hostname $ python manage.py migrate

    hostname $ python manage.py createsuperuser

    hostname $ python manage.py runserver

    hostname $ pip install psycopg2

    hostname $ psql 

    postgres=# create role myuser with createdb superuser 
    login password 'myuser';

    postgres=# create database mydb with owner myuser;

    postgres=# exit

然后编辑myproj\settings.py，运行命令python manage.py makemigrations myapp，出现下面的错误

Traceback (most recent call last):
  File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py", line 155, in get_app_config
    return self.app_configs[app_label]
KeyError: 'admin'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 21, in <module>
    main()
  File "manage.py", line 17, in main
    execute_from_command_line(sys.argv)
  File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 401, in execute_from_command_line
    utility.execute()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\__init__.py", line 395, in execute self.fetch_command(subcommand).run_from_argv(self.argv)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 328, in run_from_argv
    self.execute(*args, **cmd_options)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 366, in execute
    self.check()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 392, in check
    all_issues = self._run_checks(

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\management\base.py", line 382, in _run_checks
    return checks.run_checks(**kwargs)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\registry.py", line 72, in run_checks
    new_errors = check(app_configs=app_configs)

 File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py", line 13, in check_url_config
    return check_resolver(resolver)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\core\checks\urls.py", line 23, in check_resolver
    return check_method()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 407, in check
    for pattern in self.url_patterns:

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 588, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 48, in __get__
    res = instance.__dict__[self.name] = self.func(instance)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\urls\resolvers.py", line 581, in urlconf_module
    return import_module(self.urlconf_name)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\importlib\__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)

File "<frozen importlib._bootstrap>", line 1014, in _gcd_import

File "<frozen importlib._bootstrap>", line 991, in _find_and_load

File "<frozen importlib._bootstrap>", line 975, in _find_and_load_unlocked

File "<frozen importlib._bootstrap>", line 671, in _load_unlocked

 File "<frozen importlib._bootstrap_external>", line 783, in exec_module

File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed

File "C:\myproj\myproj\urls.py", line 20, in <module>
    path('admin/', admin.site.urls),

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\utils\functional.py", line 224, in inner
    self._setup()

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\contrib\admin\sites.py", line 537, in _setup
    AdminSiteClass = import_string(apps.get_app_config('admin').default_site)

File "C:\Users\userpc\AppData\Local\Programs\Python\Python38\lib\site-packages\django\apps\registry.py", line 162, in get_app_config
    raise LookupError(message)

LookupError: No installed app with label 'admin'.

---

我能做些什么吗？？？我错过了什么吗？？？我正在尝试使用较旧版本的django，如2.2.10，但它仍然不起作用，当发生此错误时，我使用了django和python的新版本以及postgresql

您的应用程序正在导入管理员，但django管理员在您的settings.py中不存在

将其添加到已安装的应用程序中：

INSTALLED_APPS=['django.contrib.admin'，'your.other.applications.follow']

看起来是一个解决方案。这是默认情况下呈现的，不确定OP删除它的原因。呃，我只按照讲师给我的说明进行操作，但确实有效，但现在我遇到了一个错误，称为“我的应用程序”中未检测到任何更改，该怎么办--这不是一个错误。这意味着不存在数据库模型，或者已经应用了所有迁移。