JavaScript - help

help me
function onSelectionChange(e)
{
var ss= SpreadsheetApp.getActiveSpreadsheet();
var s=ss.getActiveSheet();
var r= s.getActiveCell();
var e= r.getValue();
var ss = SpreadsheetApp.getActiveSpreadsheet();
var hoja = ss.getSheets()[1];
var range = e.range;
if(range.getNumRows() === 1
&& range.getNumColumns() === 1
&& range.getCell(2,6,0,0).getValue(grafico4) === "") {
range.setBackground("NULL");
}else{
var grafico4 = hoja.newChart()
.setChartType(Charts.ChartType.GAUGE)
.addRange(hoja.getRange(e.range))
.setPosition(2,6,0,0)
.build();
hoja.insertChart(grafico4)
}
}