code: def cache(self):
          
          if not self._cache:
              use_cache = getattr(settings, 'USE_DRF_INSTANCE_CACHE', True)
              if use_cache:
                  from django.core.cache import cache
                  self._cache = cache
          return self._cache
docs: Get the Django cache interface.
  
          This allows disabling the cache with
          settings.USE_DRF_INSTANCE_CACHE=False.  It also delays import so that
          Django Debug Toolbar will record cache requests.