What is the {office building} for {occupant} of {Social Democratic Party of Germany}
What building contains the headquarters for the Social Democratic Party of Germany?
 select distinct ?sbj where { ?sbj wdt:P466 wd:Q49768 . ?sbj wdt:P31 wd:Q1021645 } 
select distinct ?subj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> ?subj . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P466> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q49768> . ?subj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q1021645> } 
What building does the German Social Democratic Party headquarters contain?