public Workbook(filePath as String, mode as WorkbookMode = WorkbookMode.READ) throws IOException:
Creates or reads a workbook.
The default mode is WorkbookMode.READ: the constructor loads an existing workbook. Use WorkbookMode.CREATE when starting a new file.
workbook = Workbook("report.xlsx", WorkbookMode.CREATE)
workbook.addWorksheet("Data")
workbook.close()