Were M1 and M3 employed by a country of nationality of a screenwriter and employed by M2
SELECT count(*) WHERE {
?x0 ^ns:people.person.nationality ?x1 .
?x1 a ns:film.writer .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
M3 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
M3 ns:people.person.employment_history/ns:business.employment_tenure.company M2
}