Question: What is the location of the airline hub where the film "Bus Stop" occurs?
Answer(s):
answer: Phoenix Sky Harbor International Airport

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ?c)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
?c ns:film.film_location.featured_in_films ns:m.02q6z1 . 
?c ns:location.location.nearby_airports ?x .
?x ns:aviation.airport.focus_city_for ns:m.0gztl .
}