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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 delete(self, cluster):
 """Deletes the cluster from persistent state. :param cluster: cluster to delete from persistent state :type cluster: :py:class:`elasticluster.cluster.Cluster` """

        path = self._get_cluster_storage_path(cluster.name)
        if os.path.exists(path):
            os.unlink(path)