Which division were the Brewers a part of in the 1987 season?
CREATE TABLE "table_key" (
  "mlb_season" text,
  "team_season" text,
  "league" text,
  "division" text,
  "finish" text,
  "wins" text,
  "losses" text,
  "win_pct" text
);
SELECT "division" FROM "table_key" WHERE "team_season"='1987';