what is the series # for the episode directed by Kelly Sandefur?
CREATE TABLE "table1_17901155_3" (
  "no_in_series" real,
  "no_in_season" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_u_s_air_date" text,
  "prod_code" text,
  "viewers_millions" text
);
SELECT MAX("no_in_series") FROM "table1_17901155_3" WHERE "directed_by"='Kelly Sandefur';