[1.8.x] Sorted imports with isort; refs #23860.

Backport of 0ed7d15563 from master

tests/generic_inline_admin/tests.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
+
 import warnings
 
 from django.contrib import admin
@@ -9,12 +10,13 @@ from django.contrib.contenttypes.admin import GenericTabularInline
 from django.contrib.contenttypes.forms import generic_inlineformset_factory
 from django.forms.formsets import DEFAULT_MAX_NUM
 from django.forms.models import ModelForm
-from django.test import RequestFactory, TestCase, ignore_warnings, override_settings
+from django.test import (
+    RequestFactory, TestCase, ignore_warnings, override_settings,
+)
 from django.utils.deprecation import RemovedInDjango19Warning
 
-# local test models
 from .admin import MediaInline, MediaPermanentInline, site as admin_site
-from .models import Episode, Media, EpisodePermanent, Category
+from .models import Category, Episode, EpisodePermanent, Media
 
 
 # Set TEMPLATE_DEBUG to True to ensure {% include %} will raise exceptions.