Unable to reach breakpoints when debugging python unittests

Hi,

I am facing 2 issues, which may be related, when debugging python unittests in Pycharm.

1. maximum recursion reached... exception ignored

2. Unable to reach any break points I set in the test. The tests were run to the end without stopping at any breakpoints. (The test exception shown below is expected.)

I tried to add pdb.set_trace() in the test and it was able to stop at the correct line.

Does anyone have any idea the reasons behind this problem or how I can investigate this? Maybe you can show me where I can find the correct log?

Thank you very much!