CREATE TABLE table_29266 ("No. in series" TEXT, "No. in season" TEXT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT)

What is the production code for the episode written by Kat Likkel & Denise Downer?
SELECT "Production code" FROM table_29266 WHERE "Written by" = 'Kat Likkel & Denise Downer'
SELECT "Production code" FROM "table_29266" WHERE "Written by" = 'Kat Likkel & Denise Downer'