public static ElementIdStrategy create(final Configuration configuration) {
        final ElementIdStrategy.Builder builder = ElementIdStrategy.build();
        if (configuration.containsKey(ID_MAKER))
            builder.idMaker((Supplier) configuration.getProperty(ID_MAKER));
        if (configuration.containsKey(ID_PROPERTY_KEY))
            builder.idPropertyKey(configuration.getString(ID_PROPERTY_KEY));
        return builder.create();
    }
This key within which to hold the user-specified identifier.  This field should be indexed by the
underlying graph.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/decoration/ElementIdStrategy.java