НЕ могу прописать URL

from django.urls import reverse
from django.db import models
from django.contrib.auth import get_user_model
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes.fields import GenericForeignKey
 
User = get_user_model()
 
 
def get_product_url(obj, viewname):
    ct_model = obj.__class__._meta.model_name
    return reverse(viewname, kwargs={'ct_model': ct_model, 'slug': obj.slug})

from django.shortcuts import render
from django.views.generic import DetailView
from .models import Notebook, Smartphone
 
 
class ProductDetailView(DetailView):
    CT_MODEL_MODEL_CLASS = {
        'notebook': Notebook,
        'smartphone': Smartphone
    }
 
    def dispatch(self, request, *args, **kwargs):
        self.model = self.CT_MODEL_MODEL_CLASS[kwargs['ct_model']]
        self.queryset = self.model._base_manager.all()
        return super().dispatch(request, *args, **kwargs)
 
    context_object_name = 'product'
    template_name = 'product_detail.html'
    slug_url_kwarg = 'slug'

from django.urls import path
from .views import test_view, ProductDetailView, test
 
urlpatterns = [
    path('', test_view, name='base'),
    path('products/<str:ct_model>/<str:slug/', ProductDetailView.as_view(), name='product_detail'),
    path('test/', test, name='test'),