docs: def _get_feed_cache(self):
          """If a recent cache exists, return it, else return None"""
          feed_cache = None
          if os.path.exists(self._feed_cache_file):
              maxage = datetime.now() - timedelta(minutes=self._cachetime)
              file_ts = datetime.fromtimestamp(os.stat(self._feed_cache_file).st_mtime)
              if file_ts > maxage:
                  try:
                      with open(self._feed_cache_file, 'rb') as cache:
                          feed_cache = cache.read()
                  finally:
                      pass
          return feed_cache