Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_21903 ( "Year(s)" real, "Final television commentator" text, "Radio commentator" text, "Spokesperson" text, "Semi-final television commentator" text, "Semi-final second television commentator" text )

### Question ###
Who was the radio commentator when the final television commentator was John Dunn?

### Accurate SQL ###

SELECT "Radio commentator" FROM table_21903 WHERE "Final television commentator" = 'John Dunn'