Question: Where is the senator from whose successor was James belford?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/successor> <http://dbpedia.org/resource/James_B._Belford> . ?x <http://dbpedia.org/ontology/region> ?uri . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Senator>}