I tried eight packages listed on the wiki http://wiki.python.org/moin/PythonInMusic.
I found that the one that music21 (http://web.mit.edu/music21/) was
- the most comprehensive
- the best tutorial
- easiest to install on windows
but as to your request for simplicity, I think it's not the simplest one. But I couldn't get any of the other programs to read midi files in a robust way (I have a variety of weird and wonderful midi file formats hanging around)
