Fredrik Lundh said:

And if we're making get_data part of the protocol, can we please have an optional get_module_names/list_modules/listdir method too?

This is why I'm concerned about get_data. It isn't necessarily enough - we've already had people ask about get_module_names and stat. Who knows what else could be useful? I suspect that some things simply aren't going to be noticed until the new import hooks get actually used "in the wild". At the moment, this issue is in the "Open Issues" section of the (not yet released) PEP. Paul