name the engine which belongs to opposed-piston engine category.
Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity Entity
m.0b9zzq m.011sn4jz m.0624k4 m.08qz0k m.0cs_n34 m.0cs_n3f m.0cs_n3q m.0cs_nly m.0g4z44g m.0g4z462 m.0p1vy9b m.0p1w15m m.068l8g
Lycoming O-540 Weslake aero-engine Lycoming O-235 Lycoming O-320 Lycoming IO-320 Lycoming AEIO-320 Lycoming AIO-320 Lycoming O-320-A1A Lycoming O-235-C1 Lycoming O-235-C1B Lycoming O-235-L2C Lycoming O-235-N2C Lycoming O-360
class entity
engineering.engine m.01zzl9
engineering.engine engineering.engine_category
Engine Opposed-piston engine
none none
engineering.engine.category
Category
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 :engineering.engine . 
VALUES ?x1 { :m.01zzl9 } 
?x0 :engineering.engine.category ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND engineering.engine (JOIN engineering.engine.category m.01zzl9))