mac os is the parent os of what operating system developer?
Entity
m.05fxn
NeXT
class class entity
computer.operating_system_developer computer.operating_system m.0511f
computer.operating_system_developer computer.operating_system computer.operating_system
Operating System Developer Operating System Mac OS
none none none
computer.operating_system.developer computer.operating_system.parent_os
Developer Parent OS
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 :computer.operating_system_developer . 
?x1 :type.object.type :computer.operating_system . 
VALUES ?x2 { :m.0511f } 
?x1 :computer.operating_system.developer ?x0 . 
?x2 :computer.operating_system.parent_os ?x1 . 
FILTER ( ?x0 != ?x1 && ?x0 != ?x2 && ?x1 != ?x2  )
}
}
(AND computer.operating_system_developer (JOIN (R computer.operating_system.developer) (JOIN (R computer.operating_system.parent_os) m.0511f)))