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_43 ( rank INTEGER, studio_s_ VARCHAR, year VARCHAR )

### Question ###
Tell me the average rank for dharma productions before 2013

### Accurate SQL ###

SELECT AVG(rank) FROM table_name_43 WHERE studio_s_ = "dharma productions" AND year < 2013