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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 list_clusters(self):
 """List the clusters in this instance. For example: .. literalinclude:: snippets.py :start-after: [START bigtable_list_clusters_on_instance] :end-before: [END bigtable_list_clusters_on_instance] :rtype: tuple :returns: (clusters, failed_locations), where 'clusters' is list of :class:`google.cloud.bigtable.instance.Cluster`, and 'failed_locations' is a list of locations which could not be resolved. """

        resp = self._client.instance_admin_client.list_clusters(self.name)
        clusters = [Cluster.from_pb(cluster, self) for cluster in resp.clusters]
        return clusters, resp.failed_locations