old_contents: from appconf import AppConf
  from django.conf import settings
  
  
  class ImageKitConf(AppConf):
      CACHEFILE_NAMER = 'imagekit.cachefiles.namers.hash'
      SPEC_CACHEFILE_NAMER = 'imagekit.cachefiles.namers.source_name_as_path'
      CACHEFILE_DIR = 'CACHE/images'
      DEFAULT_CACHEFILE_BACKEND = 'imagekit.cachefiles.backends.Simple'
      DEFAULT_CACHEFILE_STRATEGY = 'imagekit.cachefiles.strategies.JustInTime'
  
      DEFAULT_FILE_STORAGE = None
  
      CACHE_BACKEND = None
      CACHE_PREFIX = 'imagekit:'
      USE_MEMCACHED_SAFE_CACHE_KEY = True
  
      def configure_cache_backend(self, value):
          if value is None:
              if getattr(settings, 'CACHES', None):
                  value = 'django.core.cache.backends.dummy.DummyCache' if settings.DEBUG else 'default'
              else:
                  value = 'dummy://' if settings.DEBUG else settings.CACHE_BACKEND
          return value
  
      def configure_default_file_storage(self, value):
          if value is None:
              value = settings.DEFAULT_FILE_STORAGE
          return value
  
new_contents: from appconf import AppConf
  from django.conf import settings
  
  
  class ImageKitConf(AppConf):
      CACHEFILE_NAMER = 'imagekit.cachefiles.namers.hash'
      SPEC_CACHEFILE_NAMER = 'imagekit.cachefiles.namers.source_name_as_path'
      CACHEFILE_DIR = 'CACHE/images'
      DEFAULT_CACHEFILE_BACKEND = 'imagekit.cachefiles.backends.Simple'
      DEFAULT_CACHEFILE_STRATEGY = 'imagekit.cachefiles.strategies.JustInTime'
  
      DEFAULT_FILE_STORAGE = None
  
      CACHE_BACKEND = None
      CACHE_PREFIX = 'imagekit:'
      USE_MEMCACHED_SAFE_CACHE_KEY = True
  
      def configure_cache_backend(self, value):
          if value is None:
              try:
                  from django.core.cache.backends.dummy import DummyCache
              except ImportError:
                  dummy_cache = 'dummy://'
              else:
                  dummy_cache = 'django.core.cache.backends.dummy.DummyCache'
  
              if settings.DEBUG:
                  value = dummy_cache
              else:
                  value = (
                      getattr(settings, 'CACHES', {}).get('default')
                      or getattr(settings, 'CACHE_BACKEND', None)
                      or dummy_cache
                  )
          return value
  
      def configure_default_file_storage(self, value):
          if value is None:
              value = settings.DEFAULT_FILE_STORAGE
          return value
  
subject: Improve default cache backend handling