CREATE TABLE table_29335 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( million ) " TEXT)

Who wrote the episode with the production code of 3t7255?
SELECT "Written by" FROM table_29335 WHERE "Production code" = '3T7255'
SELECT "Written by" FROM "table_29335" WHERE "Production code" = '3T7255'