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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 execution_history_focus(self, model, prop_name, info):
 """ Arranges to put execution-history widget page to become top page in notebook when execution starts and stops and resets the boolean of modification_history_was_focused to False each time this notification are observed. """

        if state_machine_execution_engine.status.execution_mode in \
                [StateMachineExecutionStatus.STARTED, StateMachineExecutionStatus.STOPPED,
                 StateMachineExecutionStatus.FINISHED]:
            if self.parent is not None and hasattr(self.parent, "focus_notebook_page_of_controller"):
                # request focus -> which has not have to be satisfied
                self.parent.focus_notebook_page_of_controller(self)

        if state_machine_execution_engine.status.execution_mode is not StateMachineExecutionStatus.STARTED:
            if not self.model.selected_state_machine_id == self.model.state_machine_manager.active_state_machine_id:
                pass
            else:
                self.update()