Man pages matching name class::mop::mixin::attributecore in section 3pm:

Class::MOP::Mixin::AttributeCore.3pm.en	debian 10 / libmoose-perl
Class::MOP::Mixin::AttributeCore.3pm.en	debian 11 / libmoose-perl
Class::MOP::Mixin::AttributeCore.3pm.en	debian 12 / libmoose-perl