The purpose of the test line of Wuhan Weizhong Bank is to evaluate the credit status and repayment ability of customers and determine the loan line or credit card line they can obtain. By testing the credit line, the bank can calculate the maximum loan line or credit card line that the customer can obtain according to the customer's credit evaluation results and related rules. This helps banks to make accurate decisions based on the principles of risk control and sustainable development when providing loans or credit card products.