question: Were M1 , M2 , and M3 founded by a editor of a film
query: SELECT count(*) WHERE {
  ?x0 ns:film.editor.film ?x1 .
  ?x1 a ns:film.film .
  M1 ns:organization.organization.founders ?x0 .
  M2 ns:organization.organization.founders ?x0 .
  M3 ns:organization.organization.founders ?x0
  }