def describe_clusters(self, cluster_identifier=None):
        clusters = self.clusters.values()
        if cluster_identifier:
            if self.clusters in cluster_identifier:
                return [self.clusters[cluster_identifier]]
            else:
                raise ClusterNotFoundError(cluster_identifier)
        return clusters
dataset/ETHPy150Open spulec/moto/moto/redshift/models.py/RedshiftBackend.describe_clusters/swapped operands of `in`