Question: Give me a count of musicians who play an instrument developed by George Beauchamp ?
SPARQL query:
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX prop: <http://dbpedia.org/property/>
PREFIX onto: <http://dbpedia.org/ontology/>
SELECT DISTINCT COUNT(?uri) WHERE { ?x prop:keyPeople <http://dbpedia.org/resource/George_Beauchamp> . ?uri onto:instrument ?x  . ?uri rdf:type onto:MusicalArtist}