Was M2 's Mexican employee a writer of M0 and M1
SELECT count(*) WHERE {
?x0 ns:film.writer.film M0 .
?x0 ns:film.writer.film M1 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
?x0 ns:people.person.nationality ns:m.0b90_r
}