question: Did a screenwriter that M1 and M2 influenced and were influenced by play M3
query: SELECT count(*) WHERE {
  ?x0 a ns:film.writer .
  ?x0 ns:film.actor.film/ns:film.performance.character M3 .
  ?x0 ns:influence.influence_node.influenced M1 .
  ?x0 ns:influence.influence_node.influenced M2 .
  ?x0 ns:influence.influence_node.influenced_by M1 .
  ?x0 ns:influence.influence_node.influenced_by M2
  }