What is the NHL team in the media market ranking number 7?
CREATE TABLE "overview_by_city" (
  "metropolitan_area" text,
  "media_market_ranking" real,
  "hosted_4_teams_since" real,
  "nfl_team_s" text,
  "mlb_team_s" text,
  "nba_team_s" text,
  "nhl_team_s" text
);
SELECT "nhl_team_s" FROM "overview_by_city" WHERE "media_market_ranking"=7;