@Override
    public ApiRequestScope lookupScope(TopicPartition key) {
        // Metadata requests can group topic partitions arbitrarily, so they can all share
        // the same request context
        return SINGLE_REQUEST_SCOPE;
    }
Base driver implementation for APIs which target partition leaders.
clients/src/main/java/org/apache/kafka/clients/admin/internals/PartitionLeaderStrategy.java