query: embed.html## Get collection specific properties 
  SELECT ?collection ?collectionLabel ?property ?propertyLabel (COUNT(DISTINCT(?painter)) as ?count) WHERE {
    ?property wikibase:propertyType wikibase:ExternalId . 
    ?property wdt:P31 wd:Q19595382 .
    ?property wdt:P31 wd:Q27918607 .
    ?property wikibase:claim ?propertyclaim .
    ?property wdt:P126 ?collection .
    ?property wdt:P2378 ?collection  .
    ?item wdt:P195 ?collection .  
    ?item wdt:P31 wd:Q3305213 . 
    ?item wdt:P170 ?painter . 
    ?painter wdt:P106 wd:Q1028181 .
    SERVICE wikibase:label { bd:serviceParam wikibase:language "en" }
  } GROUP BY ?collection ?collectionLabel ?property ?propertyLabel 
  ORDER BY ?collectionLabel 