Currently, classes that inherit for any Q* has their __doc__ attribute overridden by None when accessing it as a class member. For example: class A(QObject): """Content""" will return None, when accessing A.__doc__ but when the class is instantiated, it properly works. Fixed by a slight correction in signature_extend and extending errorhandler.make_helptext a little. Fixes: PYSIDE-1884 Change-Id: Ia35158f20768f32dfe89e6be5b519cf951277e68 Pick-to: 6.5 Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>