with which musical artist is the producer of music is the key associated ?
SELECT DISTINCT var_uri where brack_open dbr_Music_Is_the_Key_ attr_open Steve_%22Silk%22_Hurley_song attr_close dbo_producer var_x sep_dot var_x dbp_associatedActs var_uri sep_dot var_x a dbo_MusicalArtist brack_close