问django sitemap DoesNotExist at /sitemap.xml

EN

from django.contrib.sitemaps import Sitemap
from .models import Homepage


class DynamicSitemap(Sitemap):
    changefreq = "monthly"
    priority = 0.5

    def items(self):
        return Homepage.objects.all()

from first_app.sitemaps import DynamicSitemap
from django.contrib.sitemaps.views import sitemap

sitemaps = {'dynamic': DynamicSitemap()}

urlpatterns = [
    path('sitemap.xml', sitemap , {'sitemaps': sitemaps}, name='sitemaps'),
]

INSTALLED_APPS = [

    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.sites',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'tinymce',
    'first_app',
    'django.contrib.sitemaps',