code: func (bot *BotAPI) GetInviteLink(config ChatConfig) (string, error) {
  	v := url.Values{}
  
  	if config.SuperGroupUsername == "" {
  		v.Add("chat_id", strconv.FormatInt(config.ChatID, 10))
  	} else {
  		v.Add("chat_id", config.SuperGroupUsername)
  	}
  
  	resp, err := bot.MakeRequest("exportChatInviteLink", v)
  	if err != nil {
  		return "", err
  	}
  
  	var inviteLink string
  	err = json.Unmarshal(resp.Result, &inviteLink)
  
  	return inviteLink, err
  }
docs: // GetInviteLink get InviteLink for a chat