CREATE TABLE table_25843 ("Series #" FLOAT, "Season #" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT)

Which season used production code 'am10'?
SELECT COUNT("Season #") FROM table_25843 WHERE "Production code" = 'AM10'
SELECT COUNT("Season #") FROM "table_25843" WHERE "Production code" = 'AM10'