old_contents: 
  from django.contrib import admin
  from sorl.thumbnail.admin import AdminImageMixin
  
  from extensions.models import Extension, ExtensionVersion
  
  class ExtensionVersionAdmin(admin.TabularInline):
      model = ExtensionVersion
      fields = 'version', 'status',
      extra = 0
  
  class ExtensionAdmin(admin.ModelAdmin):
      list_display = 'name', 'num_versions', 'creator',
      list_display_links = 'name',
  
      def num_versions(self, ext):
          return ext.versions.count()
      num_versions.short_description = "#V"
  
      inlines = [ExtensionVersionAdmin]
  
  admin.site.register(Extension, ExtensionAdmin)
  
new_contents: 
  from django.contrib import admin
  from sorl.thumbnail.admin import AdminImageMixin
  
  from extensions.models import Extension, ExtensionVersion
  from review.models import CodeReview
  
  class CodeReviewAdmin(admin.TabularInline):
      model = CodeReview
      fields = 'reviewer', 'comments',
  
  class ExtensionVersionAdmin(admin.ModelAdmin):
      list_display = 'version', 'status',
      list_display_links = 'version',
  
      inlines = [CodeReviewAdmin]
  
  admin.site.register(ExtensionVersion, ExtensionVersionAdmin)
  
  class ExtensionVersionInline(admin.TabularInline):
      model = ExtensionVersion
      fields = 'version', 'status',
      extra = 0
  
  class ExtensionAdmin(admin.ModelAdmin):
      list_display = 'name', 'num_versions', 'creator',
      list_display_links = 'name',
  
      def num_versions(self, ext):
          return ext.versions.count()
      num_versions.short_description = "#V"
  
      inlines = [ExtensionVersionInline]
  
  admin.site.register(Extension, ExtensionAdmin)
  
subject: Add CodeReview to admin.