Here at Pycon 2008 I was lamenting to David on how Leopard's default install of Python has no IDLE interface. He clued me into how to launch it from the interpreter:
>>> import idlelib.idle
Also, from the regular shell:
python -m idlelib.idle
Wait for a few seconds, and there you have it.

By Tammi January 25, 2010 - 7:44 pm
Thank you for posting this. I’ve been going crazy trying to find IDLE. A command line launch wasn’t easy to find. Thanks again!
By ahmedshamim September 5, 2009 - 12:22 am
I tried some ide download down to my mac 10.5.8, but when i click on idle app, it does open. i tried to invoke from terminal using above mentioned instruction, but in vain. pls help, i’m mission a great deal in my class.
By GanjaManja February 17, 2009 - 4:27 pm
That’s great! no need to mess with the old, half-working versions of MacPython
By Matt January 9, 2009 - 9:07 am
I haven’t updated to 3 yet, so can’t be of much help. Good luck, please post an answer if you find one!
By brandon January 8, 2009 - 11:40 pm
hi , can’t get IDLE working on 10.5.6 with python 3 rc1
import tkinter # directory /opt/local/Library/Frameworks/Python.framework/Versions/3.0/lib/python3.0/tkinter
# /opt/local/Library/Frameworks/Python.framework/Versions/3.0/lib/python3.0/tkinter/__init__.pyc matches /opt/local/Library/Frameworks/Python.framework/Versions/3.0/lib/python3.0/tkinter/__init__.py
import tkinter # precompiled from /opt/local/Library/Frameworks/Python.framework/Versions/3.0/lib/python3.0/tkinter/__init__.pyc
** IDLE can’t import Tkinter. Your Python may not be configured for Tk. **
By Matt April 15, 2008 - 9:01 am
You’re very welcome, thanks for the thanks!
By louis April 12, 2008 - 12:18 pm
THANK YOU (for posting this)! (sorry about yelling ;-p )