query: SELECT ?item (MD5(CONCAT(str(?item),str(RAND()))) as ?random)
  WHERE
  {
    SERVICE bd:sample { ?item wdt:P17 wd:Q142 . bd:serviceParam bd:sample.limit 5000  }
    ?item (wdt:P31/wdt:P279*) wd:Q811979.
    MINUS { ?item wdt:P625 _:b1. }  
  } 
  ORDER BY ?random
  LIMIT 10