[Apologies if this is the wrong board]
I've started a Python PTP module that supports the special CHDK PTP call 0x9999 (though some variants like PTP_CHDK_(GS)etMemory are still missing) and the functions provided by libptp,
https://launchpad.net/python-ptp-chdk (Yes, I know that similar modules already exists but they did not match my expectations for a useful Python module well enough...) tar balls are available here:
https://launchpad.net/python-ptp-chdk/+milestone/0.1credits: The code borrows heavily from ptpcam and chdkptp
And thanks for all the hard work and impressive results in developing CHDK.