Fix admin for content

apps/content/admin.py

@@ -23,6 +23,7 @@ class ImageObjectAdmin(admin.ModelAdmin):
 
 class ContentChildAdmin(PolymorphicChildModelAdmin):
     base_model = Content
+    show_in_index = True
     base_fieldsets = (
         (None, {'fields': ('course', 'lesson', 'title', 'position',)}),
     )
@@ -56,12 +57,13 @@ class GalleryAdmin(ContentChildAdmin):
 @admin.register(Content)
 class ContentAdmin(PolymorphicParentModelAdmin):
     base_model = Content
+    polymorphic_list = True
     child_models = (
         Image,
         Text,
         ImageText,
         Video,
-        GalleryAdmin,
+        # GalleryAdmin,
     )