How to Access STEP Instance ID's?

[flolu]

Suppose this data is in a STEP file:

#417=ADVANCED_FACE('face_1',(#112),#405,.F.);
#418=ADVANCED_FACE('face_2',(#113),#406,.F.);
#419=ADVANCED_FACE('face_3',(#114),#407,.F.);

Then the code below would print face_1, face_2 and face_3

https://github.com/trelau/pyOCCT/blob/471913e98251d3c472b279cc3821afeb27b7f4cf/examples/import_step_names.py#L42

But how can I access the ID's of the ADVANCED_FACE instances? (#417, #418 and #419)