With pyo you can already read the analog inputs, see here. It does not seem like you can get the digital I/O at the moment, but in the meantime you can connect your buttons to analog ins.
If you need to use digitals, one option would be to write a wrapper that converts them to audio-rate floatbuffers. If you want to send to python discrete messages when a button's state changes, then you should check pyo documentation to send messages ( I assume you can do it). Ultimately, most of the code in include/DigitalChannelManager.h could be re-used for these purposes, with pyo-specific callbacks.
