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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 state_machines_del_notification(self, model, prop_name, info):
 """Relive models of closed state machine """

        if info['method_name'] == '__delitem__':
            state_machine_m = info["result"]
            try:
                self.relieve_model(state_machine_m)
            except KeyError:
                pass
            self.clean_up_tabs()