@bot.callback_query_handler(func=lambda call: call.data == "about")
def callback_about(call):
     bot.edit_message_text(chat_id=call.message.chat.id, message_id=call.message.message_id, text="Проверка")

@bot.callback_query_handler(func=lambda call: call.data in ["ru", "ua"])
def callback_country_choice(call):
    bot.send_message(call.message.chat.id, "You have chosen %s" % call.data)