This is really important for newbies.  They have no business being in the system Python folder.  And Idle is for newbies!

I was teaching an intro Python class, and tried to help a student who had been writing programs in Idle, but now could not get Python going.  It took many minutes for me to discover that he had created a new file while the shell window had focus, and innocently saved the file as math.py, without looking for a new directory to put it in.

What a pain tracking that down!