How many directors were there in total for the episode with series #62?
CREATE TABLE "season_3_1998_99" (
  "series_num" real,
  "season_num" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text
);
SELECT COUNT("directed_by") FROM "season_3_1998_99" WHERE "series_num"=62;