Qt for Python (PySide/Shiboken)

Hello, I’ve decided to test the app under Python 3.6 using pyenv and get the strange behavior. I have a Signal defined in a top-level QML widget like this ApplicationWindow { … signal backendLoaded(bool success) onBackendLoaded: { … } and emit it from the Python like this main_window = engine.rootObjects()[0] main_window.backendLoaded.emit(success) # inform the GUI All works great on 3.7 and 3.8 but on 3.6.10 I got this