How many nationalities are listed for the player Glen Irwin?
CREATE TABLE "round_three" (
  "pick_num" real,
  "player" text,
  "position" text,
  "nationality" text,
  "nhl_team" text,
  "college_junior_club_team" text
);
SELECT COUNT("nationality") FROM "round_three" WHERE "player"='Glen Irwin';