What is the number of external links with a coach named Katie Kansas?
CREATE TABLE "season_13_num_dream_bigger" (
  "season" real,
  "episode" real,
  "episode_summary" text,
  "premier_date" text,
  "external_link" text,
  "coach" text
);
SELECT COUNT("external_link") FROM "season_13_num_dream_bigger" WHERE "coach"='Katie Kansas';