Which Linda McCartney has a Stuart of electric guitar?
CREATE TABLE "instruments_played_by_band_members" (
  "paul_mc_cartney" text,
  "stuart" text,
  "mc_intosh" text,
  "whitten" text,
  "linda_mc_cartney" text
);
SELECT "linda_mc_cartney" FROM "instruments_played_by_band_members" WHERE "stuart"='electric guitar';