CREATE TABLE table_3571 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" CLOB, "Directed by" CLOB, "Written by" CLOB, "Original air date" CLOB, "Production code" FLOAT, "U.S. viewers  ( millions ) " CLOB)

How many episodes were directed by Arlene Sanford?
SELECT COUNT("Written by") FROM table_3571 WHERE "Directed by" = 'Arlene Sanford'
SELECT COUNT("Written by") FROM "table_3571" WHERE "Directed by" = 'Arlene Sanford'