old_contents: from django.contrib import admin
  
  try:
      import reversion
      AdminBase = reversion.VersionAdmin
  except ImportError:
      AdminBase = admin.ModelAdmin
  
  from .models import Box
  
  
  class BoxAdmin(AdminBase):
      list_display = ["label", "created_by", "last_updated_by", "last_updated"]
      search_fields = ["content"]
  
  
  admin.site.register(Box, BoxAdmin)
  
new_contents: from django.contrib import admin
  
  try:
      from reversion.admin import VersionAdmin as AdminBase
  except ImportError:
      AdminBase = admin.ModelAdmin
  
  from .models import Box
  
  
  class BoxAdmin(AdminBase):
      list_display = ["label", "created_by", "last_updated_by", "last_updated"]
      search_fields = ["content"]
  
  
  admin.site.register(Box, BoxAdmin)
  
subject: Update for latest django-reversion