Who directed the episode titled "Smells Like Teen Sellout"?
CREATE TABLE "table1_18054886_1" (
  "no_in_series" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "prod_code" real,
  "viewers_millions" text
);
SELECT "directed_by" FROM "table1_18054886_1" WHERE "title"='\"Smells Like Teen Sellout\"';