old_contents: from django.contrib import admin
  from .models import Notification
  
  
  @admin.register(Notification)
  class NotificationAdmin(admin.ModelAdmin):
      list_display = ('recipient', 'actor', 'verb',
                      'obj', 'target', 'read', 'deleted')
      list_filter = ('read', 'deleted', 'nf_type', 'created')
      search_fields = ('recipient__username', 'verb', 'description')
      raw_id_fields = ('recipient', )
  
      fieldsets = (
              ('Basic details',
                  {'fields': ('recipient', 'verb', 'description', 'nf_type')}),
  
              ('Actor details',
                  {'fields': ('actor_content_type', 'actor_object_id',
                              'actor_text', 'actor_url_text')}),
  
              ('Object details',
                  {'fields': ('obj_content_type', 'obj_object_id',
                              'obj_text', 'obj_url_text')}),
  
              ('Target details',
                  {'fields': ('target_content_type', 'target_object_id',
                              'target_text', 'target_url_text')}),
  
              ('Other details',
                  {'fields': ('extra', 'read', 'deleted')}),
          )
  
new_contents: from django.contrib import admin
  from .models import Notification
  
  
  @admin.register(Notification)
  class NotificationAdmin(admin.ModelAdmin):
      list_display = ('recipient', 'actor', 'verb',
                      'obj', 'target', 'read', 'deleted')
      list_filter = ('read', 'deleted', 'nf_type', 'created')
      search_fields = ('verb', 'description', 'actor_text', 'target_text')
      raw_id_fields = ('recipient', )
  
      fieldsets = (
              ('Basic details',
                  {'fields': ('recipient', 'verb', 'description', 'nf_type')}),
  
              ('Actor details',
                  {'fields': ('actor_content_type', 'actor_object_id',
                              'actor_text', 'actor_url_text')}),
  
              ('Object details',
                  {'fields': ('obj_content_type', 'obj_object_id',
                              'obj_text', 'obj_url_text')}),
  
              ('Target details',
                  {'fields': ('target_content_type', 'target_object_id',
                              'target_text', 'target_url_text')}),
  
              ('Other details',
                  {'fields': ('extra', 'read', 'deleted')}),
          )
  
subject: Remove recipeint__username field from admin to fix #40