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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 _cancelScheduledRestart(self, justification=None) -> None: """ Cancels scheduled restart :param when: time restart was scheduled to :param version: version restart scheduled for """


        if self.scheduledAction:
            why_prefix = ": "
            why = justification
            if justification is None:
                why_prefix = ", "
                why = "cancellation reason not specified"

            ev_data = self.scheduledAction
            logger.info("Cancelling restart"
                        " of node {}"
                        " scheduled on {}"
                        "{}{}"
                        .format(self.nodeName,
                                ev_data.when,
                                why_prefix,
                                why))

            self._unscheduleAction()
            self._actionLog.append_cancelled(ev_data)
            logger.info(
                "Restart of node '{}'"
                "has been cancelled due to {}".format(
                    self.nodeName, why))