为什么django会出现循环导入错误？

这个问题以前似乎有人问过，但我遇到的答案都不能解决我的问题

当我尝试使用

python manage.py runserver

运行服务器时，出现以下错误：

django.core.exceptions.ImpropertlyConfigured:包含的URLconf“tutorial.urls”中似乎没有任何模式。如果在文件中看到有效的模式，那么问题可能是由循环导入引起的

如果我更改models.py以使我的Item类不扩展

models.Model

，错误就会消失

以下是相关文件：

型号.py

from django.db import models
from django.contrib.auth.models import User

class Item(models.Model):
    name = models.CharField(max_length=255)
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    price = models.DecimalField(decimal_places=2)

    def __str__(self):
        return self.name

from rest_framework import serializers
from django.contrib.auth.models import User, Group
from .models import Item

class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('url', 'username', 'email', 'groups')

class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        fields = ('url', 'name')

class ItemSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Item
        fields = ('url', 'name', 'owner', 'price')

from django.contrib.auth.models import User, Group
from rest_framework import viewsets
from .serializers import UserSerializer, GroupSerializer, ItemSerializer
from .models import Item

class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer

class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer

class ItemViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows items to be viewed or edited.
    """
    queryset = Item.objects.all()
    serializer_class = ItemSerializer

from django.urls import include, path
from rest_framework import routers
from tutorial.quickstart import views

router = routers.DefaultRouter()
router.register('users', views.UserViewSet)
router.register('groups', views.GroupViewSet)
router.register('items', views.ItemViewSet)

urlpatterns = [
    path('', include(router.urls)),
    path('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
]

序列化程序.py

from django.db import models
from django.contrib.auth.models import User

class Item(models.Model):
    name = models.CharField(max_length=255)
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    price = models.DecimalField(decimal_places=2)

    def __str__(self):
        return self.name

from rest_framework import serializers
from django.contrib.auth.models import User, Group
from .models import Item

class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('url', 'username', 'email', 'groups')

class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        fields = ('url', 'name')

class ItemSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Item
        fields = ('url', 'name', 'owner', 'price')

from django.contrib.auth.models import User, Group
from rest_framework import viewsets
from .serializers import UserSerializer, GroupSerializer, ItemSerializer
from .models import Item

class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer

class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer

class ItemViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows items to be viewed or edited.
    """
    queryset = Item.objects.all()
    serializer_class = ItemSerializer

from django.urls import include, path
from rest_framework import routers
from tutorial.quickstart import views

router = routers.DefaultRouter()
router.register('users', views.UserViewSet)
router.register('groups', views.GroupViewSet)
router.register('items', views.ItemViewSet)

urlpatterns = [
    path('', include(router.urls)),
    path('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
]

视图.py

from django.db import models
from django.contrib.auth.models import User

class Item(models.Model):
    name = models.CharField(max_length=255)
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    price = models.DecimalField(decimal_places=2)

    def __str__(self):
        return self.name

from rest_framework import serializers
from django.contrib.auth.models import User, Group
from .models import Item

class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('url', 'username', 'email', 'groups')

class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        fields = ('url', 'name')

class ItemSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Item
        fields = ('url', 'name', 'owner', 'price')

from django.contrib.auth.models import User, Group
from rest_framework import viewsets
from .serializers import UserSerializer, GroupSerializer, ItemSerializer
from .models import Item

class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer

class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer

class ItemViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows items to be viewed or edited.
    """
    queryset = Item.objects.all()
    serializer_class = ItemSerializer

from django.urls import include, path
from rest_framework import routers
from tutorial.quickstart import views

router = routers.DefaultRouter()
router.register('users', views.UserViewSet)
router.register('groups', views.GroupViewSet)
router.register('items', views.ItemViewSet)

urlpatterns = [
    path('', include(router.urls)),
    path('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
]

url.py

from django.db import models
from django.contrib.auth.models import User

class Item(models.Model):
    name = models.CharField(max_length=255)
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    price = models.DecimalField(decimal_places=2)

    def __str__(self):
        return self.name

from rest_framework import serializers
from django.contrib.auth.models import User, Group
from .models import Item

class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        fields = ('url', 'username', 'email', 'groups')

class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        fields = ('url', 'name')

class ItemSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Item
        fields = ('url', 'name', 'owner', 'price')

from django.contrib.auth.models import User, Group
from rest_framework import viewsets
from .serializers import UserSerializer, GroupSerializer, ItemSerializer
from .models import Item

class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer

class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer

class ItemViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows items to be viewed or edited.
    """
    queryset = Item.objects.all()
    serializer_class = ItemSerializer

from django.urls import include, path
from rest_framework import routers
from tutorial.quickstart import views

router = routers.DefaultRouter()
router.register('users', views.UserViewSet)
router.register('groups', views.GroupViewSet)
router.register('items', views.ItemViewSet)

urlpatterns = [
    path('', include(router.urls)),
    path('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
]

---

你也能包括视图吗？因为您只在URL.py中导入视图，所以问题可能就在那里的某个地方。添加了views.py。就像这样，我觉得很好。在您的设置文件中，ROOT_URLCONF设置为什么？你的项目结构是什么？