How many points when John Vopni won a season before 1977?
CREATE TABLE "mjhl_scoring_champions" (
  "season" real,
  "winner" text,
  "team" text,
  "goals" text,
  "assists" text,
  "points" text
);
SELECT "points" FROM "mjhl_scoring_champions" WHERE "season"<1977 AND "winner"='john vopni';