How many # were written by david hoselton?
CREATE TABLE "table1_22904752_1" (
  "no" real,
  "num" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "u_s_viewers_million" text,
  "rank_week" text,
  "original_air_date" text
);
SELECT MAX("num") FROM "table1_22904752_1" WHERE "written_by"='David Hoselton';