import xlwt

def tool_excel_export(self, request, obj, button):
    response = HttpResponse(mimetype="application/ms-excel")
    response['Content-Disposition'] = 'attachment; filename=file.xls'
    
    wb = xlwt.Workbook()
    ws = wb.add_sheet('Sheetname')
    
    ws.write(0, 0, 'Firstname')
    ws.write(0, 1, 'Surname')
    ws.write(1, 0, 'Hans')
    ws.write(1, 1, 'Muster')

    wb.save(response)
    return response