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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_offset_topic_partition_count(kafka_config):
 """Given a kafka cluster configuration, return the number of partitions in the offset topic. It will raise an UnknownTopic exception if the topic cannot be found."""

    metadata = get_topic_partition_metadata(kafka_config.broker_list)
    if CONSUMER_OFFSET_TOPIC not in metadata:
        raise UnknownTopic("Consumer offset topic is missing.")
    return len(metadata[CONSUMER_OFFSET_TOPIC])