code: func (b *Bot) Notify(recipient Recipient, action ChatAction) error {
  	params := map[string]string{
  		"chat_id": recipient.Recipient(),
  		"action":  string(action),
  	}
  
  	respJSON, err := b.Raw("sendChatAction", params)
  	if err != nil {
  		return err
  	}
  
  	return extractOkResponse(respJSON)
  }
docs: // Notify updates the chat action for recipient.
  //
  // Chat action is a status message that recipient would see where
  // you typically see "Harry is typing" status message. The only
  // difference is that bots' chat actions live only for 5 seconds
  // and die just once the client recieves a message from the bot.
  //
  // Currently, Telegram supports only a narrow range of possible
  // actions, these are aligned as constants of this package.