question: Did a German person direct and write M1 , M2 , M3 , and M4
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x0 ns:film.director.film M1 .
  ?x0 ns:film.director.film M2 .
  ?x0 ns:film.director.film M3 .
  ?x0 ns:film.director.film M4 .
  ?x0 ns:film.writer.film M1 .
  ?x0 ns:film.writer.film M2 .
  ?x0 ns:film.writer.film M3 .
  ?x0 ns:film.writer.film M4 .
  ?x0 ns:people.person.nationality ns:m.0345h
  }