What is the season # for the episode with air date february 2, 1970?
CREATE TABLE "season_15_1969_70" (
  "series_num" real,
  "season_num" real,
  "title" text,
  "director" text,
  "writer_s" text,
  "airdate" text
);
SELECT MAX("season_num") FROM "season_15_1969_70" WHERE "airdate"='February 2, 1970';