Who is every driver for the location of Estoril Circuit?
CREATE TABLE "2008_season" (
  "sf_round" real,
  "country" text,
  "location" text,
  "date" text,
  "driver" text,
  "race_1_pts" real,
  "race_2_pts" real,
  "race_total_pts" real
);
SELECT "driver" FROM "2008_season" WHERE "location"='Estoril Circuit';