old_contents: from django.contrib import admin
  from music.models import Music
  
  
  class MusicAdmin(admin.ModelAdmin):
      list_display = ('name', 'count', 'music_id', 'source', 'duration', 'last_play', 'dead_link', 'thumbnail', 'room', 'timer_start', 'timer_end')
      actions = ('add_music',)
  
      def has_add_permission(self, request):
          return False
  
      def add_music(self, request, queryset):
          for music in queryset:
              music.room.play(music)
          return
  
  admin.site.register(Music, MusicAdmin)
  
new_contents: from django.contrib import admin
  from music.models import Music
  
  from music.serializers import MusicSerializer
  
  
  class MusicAdmin(admin.ModelAdmin):
      list_display = ('name', 'count', 'music_id', 'source', 'duration', 'last_play', 'dead_link', 'thumbnail', 'room', 'timer_start', 'timer_end')
      actions = ('add_music',)
  
      def has_add_permission(self, request):
          return False
  
      def add_music(self, request, queryset):
          for music in queryset:
              music.room.add_music(**MusicSerializer(music).data)
          return
  
  admin.site.register(Music, MusicAdmin)
  
subject: fix add music