CREATE TABLE table_26539 ("No. in series" FLOAT, "No. in season" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" FLOAT)

How many production codes have an original airdate of November 16, 1990?
SELECT COUNT("Production code") FROM table_26539 WHERE "Original air date" = 'November 16, 1990'
SELECT COUNT("Production code") FROM "table_26539" WHERE "Original air date" = 'November 16, 1990'