I think it must be eb600.py: looks like maybe the Pocketbook devices were based on a Netronics device; however, all the EB600 subclasses seem to fall back on the methods of its base class (USBMS), so I'm looking at that and Device and CLI (which it inherits from); I guess I might have to create a new subclass of USBMS for my Pocketbook model? Not clear to to me yet how that (or any) driver class maps calibre columns to device book attributes (eg. for my Pocketbook ("Verge Pro") the tags column is mapped to the 'Genre' attribute (which I override via a plugboard), but I don't know where that (tags -> 'Genre') mapping is defined; I guess I would need a crash course in the calibre codebase to get much further
