Newbies question

[Mouali rabii sbai]

Hello,

Can anybody telling me how to execute an program with python.

I explain, i have download the Grail Browser, making 100% in python.
In the readme file, they tell to just click on grail.py, but i have nothing
with this.
In the IDLE, i've pass this command :
exec python c:\program files\python\grail\grail.py
But i have an error.

If it's not true, what shall i do?

Thanks