docs: public ClusterConfigration getConfig(String key)
        throws MemcachedException, InterruptedException, TimeoutException {
      Command cmd = this.commandFactory.createAWSElasticCacheConfigCommand("get", key);
      final Session session = this.sendCommand(cmd);
      this.latchWait(cmd, opTimeout, session);
      cmd.getIoBuffer().free();
      this.checkException(cmd);
      String result = (String) cmd.getResult();
      if (result == null) {
        throw new MemcachedException("Operation fail,may be caused by networking or timeout");
      }
      return AWSUtils.parseConfiguration(result);
    }