question: What film producer that was influenced by M2 and was influenced by a film producer wrote M1
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.producer .
  ?x0 ns:film.writer.film M1 .
  ?x0 ns:influence.influence_node.influenced_by ?x1 .
  ?x0 ns:influence.influence_node.influenced_by M2 .
  ?x1 a ns:film.producer
  }