Clearing the screen

[Ishwor]

Hi i use IDLE to code Python in my machine. What i haven't been able
to do is call an in-built function called clear()/cls()/clr() because
it mightn't exist. so what i did is coded my own function called cls()
as such
>>> def cls():
	for i in range(1,40):
		print " ";

now that does the job very nicely and i get cleared screen but what i
really want to achieve it everytime i start IDLE, without importing
any module, i want to be able to do just cls() and be able to clear
the screen. Is that achievable? Does that have mean i have to tinker a
bit with in-builts??

Thank you.

-- 
cheers,
Ishwor Gurung