code: def get_cache(self, request):
          
  
          # try and get the cached GET response
          cache_key = self.cache_key(request)
          cached_response = cache.get(cache_key, None)
          # if it wasn't found and we are looking for a HEAD, try looking for a corresponding GET
          if cached_response is None and request.method == 'HEAD':
              cache_key = self.cache_key(request, 'GET')
              cached_response = cache.get(cache_key, None)
          if cached_response is None:
              return None, None
          if cached_response[1] < time.time() - settings.BETTERCACHE_LOCAL_POSTCHECK:
              return cached_response[0], True
          return cached_response[0], False
docs: Attempts to get a response from cache, returns a tuple of the response and whether it's expired
              If there is no cached response return (None, None,)