This site has a few nice little PyObjC samples.
One of them shows how to play a sound using AppKit’s NSSound. This is exactly what I was trying to do today.

And since PyObjC is built-in in 10.5, no addtional software is required.

Python is already batteries included, with PyObjC, you’ve got batteries galore.

ipython output:

In [1]: from AppKit import NSSound
In [2]: sound = NSSound.alloc()
In [3]: sound.initWithContentsOfFile_byReference_('/System/Library/CoreServices/Setup Assistant.app/Contents/Resources/TransitionSection.bundle/Contents/Resources/intro-sound.mp3', True)
Out[3]:
In [4]: sound.play()
Out[4]: True
In [5]: sound.stop()
Out[5]: True