default boolean hasSerializer() {
        return null != getFunctionOfShadedKryo() ||
                null != getSerializerShim() ||
                null != getShadedSerializer();
    }
Returns true if at least one of {@link #getShadedSerializer()}, {@link #getSerializerShim()}, or
{@link #getFunctionOfShadedKryo()} is non null.  Returns false if all are null.

@return whether a serializer is defined for this type registration
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/io/gryo/TypeRegistration.java