fix import

district/models.py

@@ -8,6 +8,7 @@ from django.conf import settings
 from django.http import HttpResponseRedirect
 from modelcluster.contrib.taggit import ClusterTaggableManager
 from modelcluster.fields import ParentalKey
+from django.contrib import messages
 from wagtail.contrib.routable_page.models import RoutablePageMixin
 from taggit.models import TaggedItemBase
 from wagtail.admin.panels import (