private void collectLookupRequests(List<RequestSpec<K>> requests) {
        collectRequests(
            requests,
            lookupMap,
            (keys, scope) -> Collections.singletonList(new AdminApiHandler.RequestAndKeys<>(handler.lookupStrategy().buildRequest(keys), keys))
        );
    }
Callback that is invoked when a `Call` is failed.
clients/src/main/java/org/apache/kafka/clients/admin/internals/AdminApiDriver.java