Question: Who is the prime minister of Japan in 2011 who was a member of the Socialist Democratic Federation?
Answer(s):
answer: Naoto Kan

SPARQL query:
PREFIX ns: <http://rdf.freebase.com/ns/>
SELECT DISTINCT ?x
WHERE {
FILTER (?x != ns:m.03_3d)
FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.03_3d ns:government.governmental_jurisdiction.governing_officials ?y .
?y ns:government.government_position_held.office_holder ?x .
?y ns:government.government_position_held.basic_title ns:m.060bp .
FILTER(NOT EXISTS {?y ns:government.government_position_held.from ?sk0} || 
EXISTS {?y ns:government.government_position_held.from ?sk1 . 
FILTER(xsd:datetime(?sk1) <= "2011-12-31"^^xsd:dateTime) })
FILTER(NOT EXISTS {?y ns:government.government_position_held.to ?sk2} || 
EXISTS {?y ns:government.government_position_held.to ?sk3 . 
FILTER(xsd:datetime(?sk3) >= "2011-01-01"^^xsd:dateTime) })
?x ns:government.politician.party ?c .
?c ns:government.political_party_tenure.party ns:m.063_w52 . 
}