How to use the @lumino/datagrid.BasicMouseHandler function in @lumino/datagrid

dataModel: model2,
    selectionMode: 'column'
  });

  let grid3 = new DataGrid({ stretchLastColumn: true });
  grid3.cellRenderers.update({ 'body': fgColorFloatRenderer });
  grid3.dataModel = model3;
  grid3.keyHandler = new BasicKeyHandler();
  grid3.mouseHandler = new BasicMouseHandler();
  grid3.selectionModel = new BasicSelectionModel({ dataModel: model3 });

  let grid4 = new DataGrid({ style: lightSelectionStyle });
  grid4.cellRenderers.update({ 'body': bgColorFloatRenderer });
  grid4.dataModel = model4;
  grid4.keyHandler = new BasicKeyHandler();
  grid4.mouseHandler = new BasicMouseHandler();
  grid4.selectionModel = new BasicSelectionModel({ dataModel: model4 });

  let grid5 = new DataGrid({
    style: greenStripeStyle,
    defaultSizes: {
      rowHeight: 32,
      columnWidth: 128,
      rowHeaderWidth: 64,
      columnHeaderHeight: 32
    }
  });
  grid5.dataModel = model5;
  grid5.keyHandler = new BasicKeyHandler();
  grid5.mouseHandler = new BasicMouseHandler();
  grid5.selectionModel = new BasicSelectionModel({
    dataModel: model5,