question: Were M2 and M4 employed by M3 and employed by M0 's German writer 's employer
query: SELECT count(*) WHERE {
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
  ?x1 ns:film.writer.film M0 .
  ?x1 ns:people.person.nationality ns:m.0345h .
  M2 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
  M2 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  M4 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
  M4 ns:people.person.employment_history/ns:business.employment_tenure.company M3
  }