[Mailman-Developers] fqdn_listname - is it strict in what type of input it accepts?

As I understand it, fqdn_listname is effectively the email address of a mailing list. i.e. testlist@example.org

The RFC 2369 list-id is the same thing but with a dot instead of an @ symbol. i.e. testlist.example.org

My question: is Mailman strict about accepting only email addresses in fqdn_listname fields? Or does it also accept RFC 2369 list-id in fqdn_listname fields?

I’m trying to wrap my head around some inconsistencies where some methods that use fqdn_listname seem to accept list-id, bt I can’t see how it possible to determine domain from a list-id, so how is it possible to accept either in a fqdn_listname field?

thanks

as