What was the losing hand where the winning hand was 7h 7s?
CREATE TABLE "main_event_winners" (
  "year" real,
  "winner" text,
  "winning_hand" text,
  "prize_money" text,
  "entrants" real,
  "runner_up" text,
  "losing_hand" text
);
SELECT "losing_hand" FROM "main_event_winners" WHERE "winning_hand"='7h 7s';