Version 3.4 of the Python3 module MIDI.py is available through
  http://www.pjb.com.au/midi/MIDI.html
and is believed to be pretty stable - in other words, I've
actually tested it :-)  (against Sean Burke's MIDI-Perl CPAN
module) and it passes the tests.  It's used by midisox:
  http://www.pjb.com.au/midi/midisox.html
which can therefore also be considered increasingly stable.

MIDI.py breaks out the .mid data into a simple list-of-lists
structure, e.g. (in the closer-to-the-data "opus" format)
    [ 96, # Ticks
        [ # Track 0...
            ['note_on', 6, 1, 60, 100],
            ['note_off', 192, 1, 60, 100]
        ]
    ]
which you can manipulate using all the resources of Python3,
and then reconvert into MIDI.

Peter

-- 
Peter Billam     www.pjb.com.au    www.pjb.com.au/comp/contact.html
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