Was a French screenwriter that M1 and M2 were written by and produced by a writer and editor of M3
SELECT count(*) WHERE {
?x0 a ns:film.writer .
?x0 ns:film.editor.film M3 .
?x0 ns:film.producer.film|ns:film.production_company.films M1 .
?x0 ns:film.producer.film|ns:film.production_company.films M2 .
?x0 ns:film.writer.film M1 .
?x0 ns:film.writer.film M2 .
?x0 ns:film.writer.film M3 .
?x0 ns:people.person.nationality ns:m.0f8l9c
}