dk.ExecutionContext.create(credentials),
       ReorderPages = PDFToolsSdk.ReorderPages,
       reorderPagesOperation = ReorderPages.Operation.createNew(),
       pageRanges = new PDFToolsSdk.PageRanges();

 reorderPagesOperation.setInput(PDFToolsSdk.FileRef.createFromLocalFile('~/Documents/reorderPagesOperationInput.pdf',
 	ReorderPages.SupportedSourceFormat.pdf));
 pageRanges.addSinglePage(3);
 pageRanges.addPageRange(1,2);
 reorderPagesOperation.setPagesOrder(pageRanges);

 reorderPagesOperation.execute(