code: function datenum(v, date1904) {
          // console.log(v)
          if (date1904) v += 1462;
          let epoch = Date.parse(v);
          return (epoch - new Date(Date.UTC(1899, 11, 30))) / (24 * 60 * 60 * 1000);
      }
docs: opens a workbook from the specified location
  @function
  @param {number} v - worksheet.
  @param {boolean} date1904 - rows to be fetched.
  @return {object} contentsJson - returns a JS Date object