public byte[] GenerateCardReports(List<Card> cards, List<List> lists, List<string> users)
 {
     // Opening the Excel template...
     using (var fs = new MemoryStream())
     {
         var templateWorkbook = new HSSFWorkbook();
         var sheet = templateWorkbook.CreateSheet("Sheet1");
         sheet.CreateHeader().AddReports(cards, lists, users);
         sheet.ForceFormulaRecalculation = true;
         return templateWorkbook.CreateRepsonse();
     }
 }