old_contents: from celery_haystack.indexes import CelerySearchIndex
  from haystack import indexes
  
  from .models import Album, Single
  
  
  class ReleaseIndex(CelerySearchIndex, indexes.Indexable):
      text = indexes.NgramField(document=True, use_template=True)
      model = indexes.CharField(model_attr='_meta__verbose_name_plural', faceted=True)
      romanized_name = indexes.CharField(model_attr='romanized_name')
      name = indexes.CharField(model_attr='name')
  
      def index_queryset(self, using=None):
          qs = super(ReleaseIndex, self).index_queryset(using=using)
          qs = qs.prefetch_related('participating_idols', 'participating_groups')
          return qs
  
  
  class AlbumIndex(ReleaseIndex):
      def get_model(self):
          return Album
  
  
  class SingleIndex(ReleaseIndex):
      def get_model(self):
          return Single
  
new_contents: from celery_haystack.indexes import CelerySearchIndex
  from haystack import indexes
  
  from .models import Album, Single
  
  
  class ReleaseIndex(CelerySearchIndex, indexes.SearchIndex):
      text = indexes.NgramField(document=True, use_template=True)
      model = indexes.CharField(model_attr='_meta__verbose_name_plural', faceted=True)
      romanized_name = indexes.CharField(model_attr='romanized_name')
      name = indexes.CharField(model_attr='name')
  
      class Meta:
          abstract = True
  
      def index_queryset(self, using=None):
          qs = super(ReleaseIndex, self).index_queryset(using=using)
          qs = qs.prefetch_related('participating_idols', 'participating_groups')
          return qs
  
  
  class AlbumIndex(ReleaseIndex, indexes.Indexable):
      def get_model(self):
          return Album
  
  
  class SingleIndex(ReleaseIndex, indexes.Indexable):
      def get_model(self):
          return Single
  
subject: Make this work again.