text: export function generateHeader(index) {
      const asciiFirstLetter = 65;
      const lettersCount = 26;
      let div = index + 1;
      let label = '';
      let pos;
      while (div > 0) {
          pos = (div - 1) % lettersCount;
          label = String.fromCharCode(asciiFirstLetter + pos) + label;
          div = parseInt(((div - pos) / lettersCount).toString(), 10);
      }
      return label.toLowerCase();
  }
  
  export function generateFakeDataObject(rowsNumber, colsNumber) {
      const result = [];
      const columns = {};
      const all = colsNumber * rowsNumber;
      for (let j = 0; j < all; j++) {
          let col = j%colsNumber;
          let row = j/colsNumber|0;
          if (!result[row]) {
              result[row] = {};
          }
          if (!columns[col]) {
              columns[col] = {
                  name: generateHeader(col),
                  prop: col,
                  pin: j === 0 ? 'colPinStart' : j === 20 ? 'colPinEnd' : undefined,
                  sortable: true,
              }
          }
          result[row][col] = row + ':' + col;
          if (col === 0) {
              columns[col].rowDrag = true;
              // columns[col].order = 'asc';
          }
          if (col === 5) {
              columns[col].autoSize = true;
          }
      }
      const pinnedTopRows = result[3] && [result[3]] || [];
      if (pinnedTopRows) {
          pinnedTopRows[0][0] = 'top';
      }
      const pinnedBottomRows = result[1] && [result[1]] || [];
      if (pinnedBottomRows) {
          pinnedBottomRows[0][0] = 'bottom';
      }
      let headers = Object.keys(columns).map((k) => columns[k]);
  
      const grouped = headers.splice(1, 4);
      const grouped2 = grouped.splice(0, 2);
      grouped.push({
          name: 'Grouped2',
          children: grouped2
      });
      headers.splice(6, 0, ...[{
          name: 'Grouped',
          children: grouped
      }]);
      /* 
      const grouped4 = headers.splice(1, 3);
      */ 
      /*  */
      /*
      headers.splice(1, 0, ...[{
          name: 'Grouped3',
          children: grouped4
      }]); */
      return {
          rows: result,
          pinnedTopRows,
          pinnedBottomRows,
          headers
      };
  }
  