public static RawTaggedFieldWriter forFields(List<RawTaggedField> fields) {
        if (fields == null) {
            return EMPTY_WRITER;
        }
        return new RawTaggedFieldWriter(fields);
    }
The RawTaggedFieldWriter is used by Message subclasses to serialize their
lists of raw tags.
clients/src/main/java/org/apache/kafka/common/protocol/types/RawTaggedFieldWriter.java