How to use the node-opcua-address-space.AddressSpace.create function in node-opcua-address-space

const engine = this;
    assert(!engine.addressSpace); // check that 'initialize' has not been already called

    engine.status = "initializing";

    options = options || {};
    assert(_.isFunction(callback));

    options.nodeset_filename = options.nodeset_filename || nodesets.standard_nodeset_file;

    const startTime = new Date();

    debugLog("Loading ", options.nodeset_filename, "...");

    engine.addressSpace = AddressSpace.create();

    // register namespace 1 (our namespace);
    const serverNamespace = engine.addressSpace.registerNamespace(engine.serverNamespaceUrn);
    assert(serverNamespace.index === 1);

    generateAddressSpace(engine.addressSpace, options.nodeset_filename, () => {

      if (!engine.addressSpace) {
        throw new Error("Internal error");
      }
      const addressSpace = engine.addressSpace;

      const endTime = new Date();
      debugLog("Loading ", options.nodeset_filename, " done : ",
        endTime.getTime() - startTime.getTime(), " ms");