Which region 1 has 12 Episodes and a Region 2 of 18 August 2008?
CREATE TABLE "dvd_releases" (
  "dvd_title" text,
  "no_of_discs" real,
  "year" text,
  "no_of_episodes" real,
  "region_1" text,
  "region_2" text,
  "region_4" text
);
SELECT "region_1" FROM "dvd_releases" WHERE "no_of_episodes"=12 AND "region_2"='18 august 2008';