updater = Updater(TOKEN)

def bottom(bot, update):
    global command
    print("botoom function called")
    counter = 0
    keyboard_list = [[KeyboardButton("about us")],
                     [KeyboardButton("MBTI test")]]
    markup = ReplyKeyboardMarkup(keyboard_list)
    chat_id = update.message.chat_id
    bot.sendMessage(chat_id=chat_id,text='Hi welcome to my bot',reply_markup=markup)

def news(bot,update):
    option = update.message.text
    chat_id = update.message.chat_id
    print ("new function run")
    print (option)
    if option == 'about us':
        keyboard_list = [[KeyboardButton("return")]]
        markup = ReplyKeyboardMarkup(keyboard_list)
        if option == 'return':
            updater.dispatcher.add_handler(MessageHandler([Filters.text],bottom))

        bot.sendMessage(chat_id,text='you chose about us',reply_markup=markup)

    elif option == 'MBTI test':
        bot.sendMessage(chat_id,'you chose mbti test')

updater.dispatcher.add_handler(CommandHandler('start',bottom))
updater.dispatcher.add_handler(MessageHandler([Filters.text], news))
updater.start_polling()