code: def _GetUrl(self, url_id, cache, database):
      
      url_cache_results = cache.GetResults('url')
      if not url_cache_results:
        result_set = database.Query(self.URL_CACHE_QUERY)
  
        cache.CacheQueryResults(
            result_set, 'url', 'id', ('url', 'rev_host'))
        url_cache_results = cache.GetResults('url')
  
      url, reverse_host = url_cache_results.get(url_id, ['', ''])
  
      if not url:
        return ''
  
      hostname = self._ReverseHostname(reverse_host)
      return '{0:s} ({1:s})'.format(url, hostname)
docs: Retrieves an URL from a reference to an entry in the from_visit table.
  
      Args:
        url_id (str): identifier of the visited URL.
        cache (SQLiteCache): cache.
        database (SQLiteDatabase): database.
  
      Returns:
        str: URL and hostname.