question: Who was a cinematographer that M2 and M3 starred
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.cinematographer .
  ?x0 a ns:people.person .
  ?x0 ns:film.actor.film/ns:film.performance.film M2 .
  ?x0 ns:film.actor.film/ns:film.performance.film M3
  }