CREATE TABLE table_21903 ("Year ( s ) " FLOAT, "Final television commentator" CLOB, "Radio commentator" CLOB, "Spokesperson" CLOB, "Semi-final television commentator" CLOB, "Semi-final second television commentator" CLOB)

Who was the radio commentator when the final television commentator was John Dunn?
SELECT "Radio commentator" FROM table_21903 WHERE "Final television commentator" = 'John Dunn'
SELECT "Radio commentator" FROM "table_21903" WHERE "Final television commentator" = 'John Dunn'