old_contents: from django.contrib import admin
  
  from icekit.utils.admin.mixins import ThumbnailAdminMixin
  
  from . import models
  
  
  class ImageAdmin(ThumbnailAdminMixin, admin.ModelAdmin):
      list_display = ['description', 'title', 'thumbnail']
      list_display_links = ['description', 'thumbnail']
      filter_horizontal = ['categories', ]
      list_filter = ['categories', 'is_active', ]
      # ThumbnailAdminMixin attributes
      thumbnail_field = 'image'
      thumbnail_options = {
          'size': (150, 150),
      }
  
      def title(self, image):
          return image.title
  
      def description(self, image):
          return unicode(image)
  
  admin.site.register(models.Image, ImageAdmin)
  
new_contents: from django.contrib import admin
  
  from icekit.utils.admin.mixins import ThumbnailAdminMixin
  
  from . import models
  
  
  class ImageAdmin(ThumbnailAdminMixin, admin.ModelAdmin):
      list_display = ['description', 'title', 'thumbnail']
      list_display_links = ['description', 'thumbnail']
      filter_horizontal = ['categories', ]
      list_filter = ['categories', 'is_active', ]
      # ThumbnailAdminMixin attributes
      thumbnail_field = 'image'
      thumbnail_options = {
          'size': (150, 150),
      }
  
      def title(self, image):
          return image.title
  
      def description(self, image):
          return str(image)
  
  admin.site.register(models.Image, ImageAdmin)
  
subject: Fix use of unicode() incompatible with Python 3