old_contents: from django.contrib import admin
  
  from .models import Post
  
  
  admin.site.register(Post)
  
new_contents: from django.contrib import admin
  
  from embed_video.admin import AdminVideoMixin
  
  from .models import Post
  
  
  class PostAdmin(AdminVideoMixin, admin.ModelAdmin):
      pass
  
  
  admin.site.register(Post, PostAdmin)
  
subject: Apply admin mixin in example project