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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 todo_results_changed(self):

 """
 Synchronize todo results between editorstacks
 Refresh todo list navigation buttons
 """

        editorstack = self.get_current_editorstack()
        results = editorstack.get_todo_results()
        index = editorstack.get_stack_index()
        if index != -1:
            filename = editorstack.data[index].filename
            for other_editorstack in self.editorstacks:
                if other_editorstack is not editorstack:
                    other_editorstack.set_todo_results(filename, results)
        self.update_todo_actions()