the name of the museum director of griffith park observatory is?
Entity
m.07x6v0
Ed Krupp
class entity
architecture.museum_director m.02_4ml
architecture.museum_director architecture.museum
Museum director griffith park observatory
none none
architecture.museum_director.museum
Museum
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 :architecture.museum_director . 
VALUES ?x1 { :m.02_4ml } 
?x0 :architecture.museum_director.museum ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND architecture.museum_director (JOIN architecture.museum_director.museum m.02_4ml))