CREATE TABLE table_27637 ("Series #" FLOAT, "Title" TEXT, "Director" TEXT, "Writer" TEXT, "Air Date" TEXT, "Production Code" FLOAT)

What was the production code of the episode written by Brendan Cowell?
SELECT "Production Code" FROM table_27637 WHERE "Writer" = 'Brendan Cowell'
SELECT "Production Code" FROM "table_27637" WHERE "Writer" = 'Brendan Cowell'