Victor, *please* don't add the external import settings to CoreConfig. That struct should only contain the absolute bare minimum of settings needed to get an interpreter that *can't* access the filesystem, such that builtin modules and frozen modules work, but nothing else does.

If you need some extra structures to hold command line and environment state, that's fine, but the full external import system attributes should go in the main interpreter config, as described in https://www.python.org/dev/peps/pep-0432/#supported-configuration-settings