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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 get_meta_clusters(self, clusters):
 """ Returns a dictionary keyed off of meta cluster names, where the values are lists of clusters associated with the meta cluster name. If a meta cluster name doesn't have a port defined in the `meta_cluster_ports` attribute an error is given and the meta cluster is removed from the mapping. """

        meta_clusters = collections.defaultdict(list)

        for cluster in clusters:
            if not cluster.meta_cluster:
                continue
            meta_clusters[cluster.meta_cluster].append(cluster)

        unconfigured_meta_clusters = [
            name for name in meta_clusters.keys()
            if name not in self.meta_clusters
        ]

        for name in unconfigured_meta_clusters:
            logger.error("Meta cluster %s not configured!")
            del meta_clusters[name]

        return meta_clusters