What is the name of the artist with a Single / Pack of guitar hero track pack 1?
CREATE TABLE "downloadable_content" (
  "year" real,
  "song_title" text,
  "artist" text,
  "master_recording" text,
  "release_date" text,
  "single_pack" text
);
SELECT "artist" FROM "downloadable_content" WHERE "single_pack"='guitar hero track pack 1';