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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_partition_leaders(cluster_config):
 """Return the current leaders of all partitions. Partitions are returned as a "topic-partition" string. :param cluster_config: the cluster :type cluster_config: kafka_utils.utils.config.ClusterConfig :returns: leaders for partitions :rtype: map of ("topic-partition", broker_id) pairs """

    client = KafkaClient(cluster_config.broker_list)
    result = {}
    for topic, topic_data in six.iteritems(client.topic_partitions):
        for partition, p_data in six.iteritems(topic_data):
            topic_partition = topic + "-" + str(partition)
            result[topic_partition] = p_data.leader
    return result