def print_selection(self, *e):
        if self._root is None: return
        if self._selection is None:
            tkinter.messagebox.showerror('Print Error', 'No tree selected')
        else:
            c = self._cframe.canvas()
            for widget in self._treewidgets:
                if widget is not self._selection:
                    self._cframe.destroy_widget(widget)
            c.delete(self._selectbox)
            (x1,y1,x2,y2) = self._selection.bbox()
            self._selection.move(10-x1,10-y1)
            c['scrollregion'] = '0 0 %s %s' % (x1+20-x2, y2-y1+20)
            self._cframe.print_to_file()

            # Restore our state.
            self._treewidgets = [self._selection]
            self.clear()
            self.update()
dataset/ETHPy150Open nltk/nltk/nltk/app/chartparser_app.py/ChartResultsView.print_selection/swapped operands of `-`