What is Opponent, when Location is "Tokyo , Japan", when Method is "Decision (unanimous)", and when Record is "4-1"?
CREATE TABLE "mixed_martial_arts_record" (
  "res" text,
  "record" text,
  "opponent" text,
  "method" text,
  "event" text,
  "round" text,
  "location" text
);
SELECT "opponent" FROM "mixed_martial_arts_record" WHERE "location"='tokyo , japan' AND "method"='decision (unanimous)' AND "record"='4-1';