In a QTreeView, a node with child nodes has the ( + ) icon on the left of it.
How can I detect in MousePressEvent if the click was made on the ( + ) icon or not?

All my previous attempts have only helped me in getting the current selected Index. I am unable to gain access to the dimesnsions/position of the +/- icon to work with.
If it helps, I am trying to add a Shift + Click functionality where a node and all its children would be recursively expanded till leaf ONLY if the Shift+Click is made on the +/- sign in the tree view.