@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        SubscribedTopicDescriberImpl that = (SubscribedTopicDescriberImpl) o;
        return topicMetadata.equals(that.topicMetadata);
    }
Returns all the available racks associated with the replicas of the given partition.

@param topicId       Uuid corresponding to the partition's topic.
@param partition     Partition Id within the topic.
@return The set of racks corresponding to the replicas of the topics partition.
        If the topic Id does not exist or no partition rack information is available, an empty set is returned.
group-coordinator/src/main/java/org/apache/kafka/coordinator/group/modern/SubscribedTopicDescriberImpl.java