@Override
    public default void close() throws Exception {
        // do nothing
    }
The clone-method should be used to create immutable traversal sources with each call to a configuration "withXXX"-method.
The clone-method should clone the {@link GremlinLang}, {@link TraversalStrategies}, mutate the cloned strategies accordingly,
and then return the cloned traversal source leaving the original unaltered.

@return the cloned traversal source
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/TraversalSource.java