code: func (b *Bot) Promote(chat *Chat, member *ChatMember) error {
  	prv := member.Rights
  
  	params := map[string]string{
  		"chat_id": chat.Recipient(),
  		"user_id": member.User.Recipient(),
  	}
  
  	embedRights(params, prv)
  
  	respJSON, err := b.Raw("promoteChatMember", params)
  	if err != nil {
  		return err
  	}
  
  	return extractOkResponse(respJSON)
  }
docs: // Promote lets you update member's admin rights, such as:
  //
  //     * can change info
  //     * can post messages
  //     * can edit messages
  //     * can delete messages
  //     * can invite users
  //     * can restrict members
  //     * can pin messages
  //     * can promote members
  //