There is already a well known (unrelated) python package called Fabric!
Pippi now also includes an optional 'realtime' (and linux-only) command-based performance layer.
Fabric is a computer music system written with the Python v2.x standard library. It is intended to be used for offline/non-realtime computer music composition.
It aims to be highly portable, hackable, understandable and powerful.
A roadmap and some documentation can be found on the fabric website