ImportError：无法导入“ core.auth.api.TokenAuthentication”

Question

我一生无法弄清楚是什么原因造成的。我有一个使用Django的小型django-rest-framework项目。我正在尝试将令牌关键字从Token修改为Bearer以进行令牌认证。尽管找不到我的类继承自rest_framework.authentication.TokenAuthentication，但由于某种原因而无法找到它。虽然可以正确找到该文件，所以我确定它不是路径问题。

设置中的相关部分；

REST_FRAMEWORK = {
'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
'PAGE_SIZE': 20,
'DEFAULT_AUTHENTICATION_CLASSES': (
    'core.auth.api.TokenAuthentication',
    'rest_framework.authentication.SessionAuthentication',
    )
}

api.py文件；

from rest_framework.authentication import TokenAuthentication as RestFrameworkTokenAuthentication
from rest_framework.authtoken.models import Token
from rest_framework.authtoken.views import ObtainAuthToken as RestFrameworkObtainAuthToken
from rest_framework.response import Response


class ObtainAuthToken(RestFrameworkObtainAuthToken):
    def post(self, request, *args, **kwargs):
        serializer = self.serializer_class(data=request.data,
                                       context={'request': request})
        serializer.is_valid(raise_exception=True)
        user = serializer.validated_data['user']
        token, created = Token.objects.get_or_create(user=user)
        return Response({
            'token': token.key,
            'user_id': user.pk,
            'username': user.username
        })


class TokenAuthentication(RestFrameworkTokenAuthentication):
    keyword = 'Bearer'

错误；

项目结构；

完整追溯

(env) karuhanga@sheer-aesthete:~/Documents/Projects/Log.Realty/backend/src$ python manage.py makemigrations
Traceback (most recent call last):
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 184, in import_from_string
    return getattr(module, class_name)
AttributeError: module 'core.auth.api' has no attribute 'TokenAuthentication'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 19, in <module>
    execute_from_command_line(sys.argv)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 316, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 350, in execute
    self.check()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 379, in check
    include_deployment_checks=include_deployment_checks,
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 366, in _run_checks
    return checks.run_checks(**kwargs)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/registry.py", line 71, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/urls.py", line 13, in check_url_config
    return check_resolver(resolver)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/urls.py", line 23, in check_resolver
    return check_method()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 396, in check
    for pattern in self.url_patterns:
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/utils/functional.py", line 37, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 533, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/utils/functional.py", line 37, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 526, in urlconf_module
    return import_module(self.urlconf_name)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/src/urls.py", line 21, in <module>
    path('', include('core.urls.urls')),
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/core/urls/urls.py", line 4, in <module>
    path('api/', include('core.urls.api.urls')),
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
(env) karuhanga@sheer-aesthete:~/Documents/Projects/Log.Realty/backend/src$ python manage.py makemigrations
Traceback (most recent call last):
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 184, in import_from_string
    return getattr(module, class_name)
AttributeError: module 'core.auth.api' has no attribute 'TokenAuthentication'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 19, in <module>
    execute_from_command_line(sys.argv)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 316, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 350, in execute
    self.check()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 379, in check
    include_deployment_checks=include_deployment_checks,
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/management/base.py", line 366, in _run_checks
    return checks.run_checks(**kwargs)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/registry.py", line 71, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/urls.py", line 13, in check_url_config
    return check_resolver(resolver)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/core/checks/urls.py", line 23, in check_resolver
    return check_method()
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 396, in check
    for pattern in self.url_patterns:
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/utils/functional.py", line 37, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 533, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/utils/functional.py", line 37, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/resolvers.py", line 526, in urlconf_module
    return import_module(self.urlconf_name)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/src/urls.py", line 21, in <module>
    path('', include('core.urls.urls')),
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/core/urls/urls.py", line 4, in <module>
    path('api/', include('core.urls.api.urls')),
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/usr/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/core/urls/api/urls.py", line 3, in <module>
    from core.auth.api import ObtainAuthToken
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/src/core/auth/api.py", line 3, in <module>
    from rest_framework.authtoken.views import ObtainAuthToken as RestFrameworkObtainAuthToken
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/authtoken/views.py", line 6, in <module>
    from rest_framework.schemas import ManualSchema
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/schemas/__init__.py", line 32, in <module>
    authentication_classes=api_settings.DEFAULT_AUTHENTICATION_CLASSES,
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 227, in __getattr__
    val = perform_import(val, attr)
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 172, in perform_import
    return [import_from_string(item, setting_name) for item in val]
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 172, in <listcomp>
    return [import_from_string(item, setting_name) for item in val]
  File "/home/karuhanga/Documents/Projects/Log.Realty/backend/env/lib/python3.6/site-packages/rest_framework/settings.py", line 187, in import_from_string
    raise ImportError(msg)
ImportError: Could not import 'core.auth.api.TokenAuthentication' for API setting 'DEFAULT_AUTHENTICATION_CLASSES'. AttributeError: module 'core.auth.api' has no attribute 'TokenAuthentication'.