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 customer ( acc_type VARCHAR, acc_bal INTEGER, credit_score INTEGER )

### Question ###
For each account type, find the average account balance of customers with credit score lower than 50.

### Accurate SQL ###

SELECT AVG(acc_bal), acc_type FROM customer WHERE credit_score < 50 GROUP BY acc_type