Who is the Artist of the singles whose film genre is Country music ?
SELECT DISTINCT ?uri WHERE { ?x <http://dbpedia.org/property/genre> <http://dbpedia.org/resource/Country_music> . ?x <http://dbpedia.org/property/artist> ?uri  . ?x <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/Single>}
Country_music