On Nuitka compiler don't return sender()

Using the current version of PySide2 and compiling with Nuitka, there is a problem in the sender () method during event handling and it returns None.

This behavior has already been reported in version 1.2 and has not been fixed despite a patch [1].

It is relatively simple to apply and I think this correction will be of great importance.

[1] http://lists.qt-project.org/pipermail/pyside/2014-February/001863.html