"SystemError: NULL Object passed to Py_BuildValue" Delay() in Python

Refer to Using WaitNNN Methods in https://support.smartbear.com/testcomplete/docs/app-objects/common-tasks/waiting-process-or-window-activation.html . There are existing methods which you can use, to wait for an object to exist and timeout after a number of seconds.

Delay and aqUtils.Delay methods work fine.

Without seeing your actual code, it's difficult to provide help