"The Magic Flute" composer (6)
I believe the answer is:
mozart
'the magic flute composer' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for mozart that I've seen before include "Wolfgang Amadeus . . . . . . 18th century Austrian composer" , "'Cosi fan tutte' composer" , "Magic Flute composer" , "Greyfriars schoolboy" , "The composer can be found in an OZ mart" .)