我是一个业余的开发人员。我尝试跟踪this tutorial，在www.example.com上我有settings.py I have

CORS_ALLOWED_ORIGINS = ['http://localhost:8080']

就像视频里那样。
但是，当我尝试从前端访问服务器时，我收到错误消息
CORS策略已阻止从源"http：//localhost：8080"访问位于"http：//127.0.0.1：8000/engine"的XMLHttpRequest：请求的资源上不存在"Access-Control-Allow-Origin"标头。
感谢在SO上有很多类似的帖子，但是我不明白为什么我会有这个问题，而制作这个教程的人却没有。

• • 型号. py**

from django.db import models
from django.utils import timezone
import datetime

class Engine(models.Model):
    date = models.DateField(default=datetime.datetime(2024,1,1))

• • 序列化程序. py**

from rest_framework import serializers

from .models import Engine

class EngineSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Engine
        fields = ('id', 'date')

• • 查看次数. py**

from django.shortcuts import render

from .models import Engine
from .serializers import EngineSerializer

from rest_framework import viewsets
from rest_framework.authentication import BasicAuthentication
from rest_framework.permissions import IsAuthenticated

class EngineViewSet(viewsets.ModelViewSet):
    authentication_classes = (BasicAuthentication,)
    permission_classes = (IsAuthenticated,)
    queryset = Engine.objects.all()
    serializer_class = EngineSerializer

• • 网址. py**

from django.contrib import admin
from django.urls import path, include

from backend_app.views import EngineViewSet

from rest_framework import routers

router = routers.DefaultRouter()
router.register('engine', EngineViewSet)

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', include(router.urls))
]