machine_question: who fought in the battle of vicksburg and is the US president with presidency number of 18
question: Who fought in the Battle of Vicksburg and was the 18th US president?
sparql: PREFIX ns: <http://rdf.freebase.com/ns/>
  SELECT DISTINCT ?x
  WHERE {
  FILTER (?x != ns:m.01hf7f)
  FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
  ns:m.01hf7f ns:base.culturalevent.event.entity_involved ?x .
  ?x ns:government.us_president.presidency_number "18" . 
  }
webqsp_question: who fought in the battle of vicksburg