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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 memory. :param cluster: cluster to delete :type cluster: :py:class:`elasticluster.cluster.Cluster` """

        if cluster.name not in self.clusters:
            raise ClusterNotFound(
                "Unable to delete non-existent cluster %s" % cluster.name)
        del self.clusters[cluster.name]