Who was the coach of the Pandas when their overall record was 20-6-2?
CREATE TABLE "year_by_year" (
  "season" text,
  "coach" text,
  "conf_record" text,
  "overall" text,
  "standings" text,
  "postseason" text
);
SELECT "coach" FROM "year_by_year" WHERE "overall"='20-6-2';