CREATE TABLE table_22904 ("No." FLOAT, "#" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT, "U.S. viewers  ( million ) " TEXT)

Name the production code for viewers for 1.69
SELECT "Production code" FROM table_22904 WHERE "U.S. viewers (million)" = '1.69'
SELECT "Production code" FROM "table_22904" WHERE "U.S. viewers (million)" = '1.69'