What is the average account balance of customers with credit score below 50 for the different account types?
SELECT avg(acc_bal) ,  acc_type FROM customer WHERE credit_score  <  50 GROUP BY acc_type
SELECT avg(acc_bal) ,  acc_type FROM customer WHERE credit_score  <  50 GROUP BY acc_type
[{'avg(acc_bal)': 1000.0, 'acc_type': 'checking'}, {'avg(acc_bal)': 2000.0, 'acc_type': 'saving'}]