To get the listview an entry widget belongs to, there’s a function in the entry widget called “get owning listview” I think.
But I don’t think that would be a proper way to handle your case.
If you want to remove an item from the listview, then remove that item from the listview. That logic should go in the listview (or rather, the widget that holds the listview)
The entry widget holds the button that drops the item. In order to inform the listview that that action happened, the most practical method is to use an event dispatcher in the entry widget, which provides the item it represents, and in the listview bind to it during the generated / initialized event.