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_20967430_4 (ep VARCHAR, prod_code VARCHAR)

### Question ###
How many episodes had a production code of 5m13?

### Accurate SQL ###

SELECT COUNT(ep) FROM table_20967430_4 WHERE prod_code = "5M13"