Name the region 4 for the complete fifth series
CREATE TABLE "table1_1337525_1" (
  "complete_series" text,
  "region_1" text,
  "region_2" text,
  "region_4" text,
  "dvd_extras_and_bonus_features" text,
  "number_of_discs" real
);
SELECT "region_4" FROM "table1_1337525_1" WHERE "complete_series"='The Complete Fifth Series';