CREATE TABLE table_30533 ("No." FLOAT, "Title" CLOB, "Directed by" CLOB, "Written by" CLOB, "Original air date" CLOB, "Production code" CLOB, "U.S. viewers  ( million ) " CLOB)

Who wrote the episode with production code 2j5568?
SELECT "Written by" FROM table_30533 WHERE "Production code" = '2J5568'
SELECT "Written by" FROM "table_30533" WHERE "Production code" = '2J5568'