QGraphicsItem subclass and accessing custom properties

[been_1990]

I created several subclasses of QGraphicsItem's and added them to the scene.
How can I access their custom properties added by me using [...] ?

scene.itemAt(x_number).myproperty

scene.itemAt(x_number).myproperty

To copy to clipboard, switch view to plain text mode 

If I try creating a new placeholder subclass instance, and assigning scene.itemAt(x) to it, I receive an error: "QGraphicsItem is private"