sendMessage(chatId, text, form = {}) {
    form.chat_id = chatId;
    form.text = text;
    return this._request('sendMessage', { form });
  }
Send text message.
@param {Number|String} chatId Unique identifier for the target chat or username of the target channel (in the format `@channelusername`)
@param {String} text Text of the message to be sent
@param {Object} [options] Additional Telegram query options
@return {Promise} On success, the sent [Message](https://core.telegram.org/bots/api#message) object is returned
@see https://core.telegram.org/bots/api#sendmessage