query: #title: Use for lighthouses
  # Complex constraint from [[Property talk:P2929]]
  # Items for existing lighthouses would generally have this property
  SELECT ?item 
  WHERE
  { 
  	?item wdt:P31 wd:Q39715 . 
  	OPTIONAL { ?item wdt:P2929 ?lthorange } . filter (!BOUND(?lthorange)) 
  	MINUS { ?item wdt:P576 [] }
  }