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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 restart_complete(self, state, new_address):
        '''
        Called when we get notified that the restart has been completed by
        some agent who has volontureed to do so.
        '''
        if state.timeout_call_id:
            state.agent.cancel_delayed_call(state.timeout_call_id)
            state.timeout_call_id = None
        return self._send_restarted_notifications(new_address)