query: SELECT DISTINCT ?country (group_concat(distinct ?languageL ; separator = ", ") as ?languages) WHERE {
    ?item wdt:P31 wd:Q6256 ;
          wdt:P37 ?language .
  
    FILTER NOT EXISTS {
      ?item wdt:P37 ?y . 
      ?p wdt:P31 wd:Q6256 ;
         wdt:P37 ?y ;
         wdt:P30 wd:Q46 .
    }
    ?language rdfs:label ?languageL filter (lang(?languageL) = "en") .
    ?item rdfs:label ?country filter (lang(?country) = "en") .
  }
  GROUP BY ?country
  ORDER BY ?country