Python tests not showing failing test case

[gelpenaddict]

If the code has an infinite loop or other Python/Pycharm hanging issue (not sure exactly why but using != for ListNode's instead of is not), the test also hangs but does not print out the test case.

That makes troubleshooting very difficult as I have to put a breakpoint and run through test cases until I get to the failure.

It'd be helpful to just run the test case that failed by printing out the input before executing the test case.