What number-one single is performed by artist Pep's?
CREATE TABLE "p" (
  "artist" text,
  "country" text,
  "number_one_single_s" text,
  "year" real,
  "weeks_at_num1" real,
  "straight_to_num1" text
);
SELECT "number_one_single_s" FROM "p" WHERE "artist"='Pep''s';