Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_12 ( director VARCHAR, release_date VARCHAR, series VARCHAR, production_num VARCHAR )

### Question ###
Who was the director of the movie having a release date of 1934-09-15, an MM Series and a production number less than 6494?

### Accurate SQL ###

SELECT director FROM table_name_12 WHERE series = "mm" AND production_num < 6494 AND release_date = "1934-09-15"