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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 on_mouse_motion(self, widget, event):
 """selection on mouse over :param widget: :param Gdk.Event event: mouse motion event """

        path = self.view.get_path_at_pos(int(event.x), int(event.y))
        if path is not None:
            self.view.select_path(path)
        else:
            self.view.unselect_all()