How do I make the program to clear the screen?


There are billions of links in google with such code written in different ways. But it simply doesn't clear the screen when I tried it. What's wrong?
Can I make the program clear the screen every time and print new info so that there was no old useless info? I mean it prints the board, something changed, it clears the screen and prints the new version of board. How can I do that?

import os
clear = lambda: os.system('cls')


this seems to be impossible inside the lesson, it will work fine outside the lesson

cls is by the windows version, the codecademy server is linux, in which case it is clear (but still won't work)


I checked it from saved .py file on my pc under windows 7, python 2.7. It still doesn't work. It doesn't give any error, just ignores this command.