old_contents: from __future__ import unicode_literals
  
  from django.apps import AppConfig
  
  
  class CtfConfig(AppConfig):
      name = 'api'
  
new_contents: from __future__ import unicode_literals
  
  from django.apps import AppConfig
  
  
  class ApiConfig(AppConfig):
      name = 'api'
  
subject: modify class name