Elastic Nodes python Example - sources are wrong/not usable

The example specified on this page:

https://doc.qt.io/qtforpython-6/overviews/qtwidgets-graphicsview-elasticnodes-example.html

the sources is some mixup of c++ and python code, completely unusable

with google search I can see correct python sources on this page, I verified it is working correctly (with some simple fix below) with PySide6:

https://doc-snapshots.qt.io/qtforpython-6.0/examples/example_widgets_graphicsview_elasticnodes.html

the fix needed:

event.delta() need to be replaced to 
event.angleDelta().y()
and
matrix() need to be replaced to transform()