How many people are women's singles in the season of 2000/01?
CREATE TABLE "senior_events" (
  "season" text,
  "host" text,
  "mens_singles" text,
  "womens_singles" text,
  "mens_doubles" text,
  "womens_doubles" text
);
SELECT COUNT("womens_singles") FROM "senior_events" WHERE "season"='2000/01';