question: Was M4 a film editor whose employer employed M0 , employed M1 , and employed M2 and M3
query: SELECT count(*) WHERE {
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person M0 .
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person M1 .
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person M2 .
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person M3 .
  M4 a ns:film.editor .
  M4 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0
  }