At the moment there is no such feature in the main branch, as that was never intended to be used outside of an interactive context.
A while back I started work on a python-only version of the insteon terminal which would allow you to use the terminal utilities as a python library that you can import the standard way.
It's not complete yet, but does have all the send/receive functionality of the old terminal, and allows you to modify the modem link database (it doesn't let you modify the device link database yet though). I hope to have some free time around Christmas to finish this up and get it to feature parity with the old insteon-terminal, so hopefully I will finish this up soon (fingers crossed).
Daniel