someone who uses a violoncello is called what type of professional musician?
Entity
m.02h66dz
Cellist
class entity
music.musician_profession m.01xqw
music.musician_profession music.instrument
Musician profession violoncello
none none
music.musician_profession.instrument
Instrument
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :music.musician_profession . 
VALUES ?x1 { :m.01xqw } 
?x0 :music.musician_profession.instrument ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND music.musician_profession (JOIN music.musician_profession.instrument m.01xqw))