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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 coordinator_dead(self, error):
 """Mark the current coordinator as dead."""

        if self.coordinator_id is not None:
            log.warning("Marking the coordinator dead (node %s) for group %s: %s.",
                        self.coordinator_id, self.group_id, error)
            self.coordinator_id = None