[PyQt] selection behavior of a TableView

[Michael Wyss]

Greetings
I am currently working on a Model-View-Delegate which works fine so far 
but I'm not happy with the standard selection behavior and I can't find 
a way to modify it.
I'm using:
View: QTableView
Model QAbstractTableModel
Delegate: QItemDelegate

What I want is to change the Shift selection behavior of my TableView. 
Here an example:
What I get when selecting 1/1 shift 2/2 :
- 1 2 3 4
1 x x
2 x x

What I want when selecting 1/1 shift 2/2 :
- 1 2 3 4
1 x x x x
2 x x