return possibl base classifierrol take account wellformednessrul defin section uml spec param role given classifierrol collect possibl base collect possibl base classifi role role role model impl facad namespac role collect set collabor collabor collabor role namespac namespac ns collabor namespac model manag helper mmh model impl model manag helper collect classifi list mmh model element kind ns classifi wfr list remov mmh model element kind ns classifi role classifi singl unnam classifi role todo probabl belong critic instead collect classifi list remov arrai list classifi classifi classifi list collect classifi role classifi role omg uml uml classifi ref outermost collabor classifi role base classifi role classifi classifi role unnam elimin classifi base role role role equal list remov add classifi elimin classifi unnam role classifi role cr classifi role cr cr equal list remov add classifi list remov list remov need verifi ns parent caus except creat sequenc diagram classifi role ns uml ns ns ns namespac ns uml classifi import packag todo probabl happen automat model element kind tfm model impl facad ns list add import classifi ns list 