What is the  capital  of the  Western Roman Empire  that  start time  is  402 - 0 - 0 ?
SELECT ?obj WHERE { wd:Q42834 p:P36 ?s . ?s ps:P36 ?obj . ?s pq:P580 ?x filter(contains(?x,'402-0-0')) }
western roman empire (395-476 ad): Q42834