docs: def _load_cache(self):
          """Load existing cache and merge for updating if required."""
          if not self._disable_cache:
              if os.path.exists(self._cache_path):
                  _LOGGER.debug("Cache found at: %s", self._cache_path)
                  if os.path.getsize(self._cache_path) > 0:
                      loaded_cache = UTILS.load_cache(self._cache_path)
                      UTILS.update(self._cache, loaded_cache)
                  else:
                      _LOGGER.debug("Cache file is empty.  Removing it.")
                      os.remove(self._cache_path)
  
          self._save_cache()