What is the 1st leg of the Round that has a 2nd leg of 1-3 and Team 1 Es Tunis?
CREATE TABLE "second_round" (
  "team_1" text,
  "agg" text,
  "team_2" text,
  "1st_leg" text,
  "2nd_leg" text
);
SELECT "1st_leg" FROM "second_round" WHERE "2nd_leg"='1-3' AND "team_1"='es tunis';