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_21 (release_date VARCHAR, production_num VARCHAR, characters VARCHAR)

### Question ###
When was the film released that a less than 5038 production number and was of the character Bosko?

### Accurate SQL ###

SELECT release_date FROM table_name_21 WHERE production_num < 5038 AND characters = "bosko"