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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def list_view_on_selected(self, widget, selected_item_key):
 """ The selection event of the listView, returns a key of the clicked event. You can retrieve the item rapidly """

        self.lbl.set_text('List selection: ' + self.listView.children[selected_item_key].get_text())