Question: Name the country whose leader's deputy is Piotr Glinski?
SPARQL:
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/deputy> <http://dbpedia.org/resource/Piotr_Gliński> . ?uri <http://dbpedia.org/property/leaderName> ?x  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Country>}