code: def show(self, start_date, end_date):
          
  
          # title in the report file name
          vars = {"title": _("Time track"),
                  "start": start_date.strftime("%x").replace("/", "."),
                  "end": end_date.strftime("%x").replace("/", ".")}
          if start_date != end_date:
              filename = "%(title)s, %(start)s - %(end)s.html" % vars
          else:
              filename = "%(title)s, %(start)s.html" % vars
  
          self.dialog.set_current_name(filename)
  
          response = self.dialog.run()
  
          if response != gtk.ResponseType.OK:
              self.emit("report-chooser-closed")
              self.dialog.destroy()
              self.dialog = None
          else:
              self.on_save_button_clicked()
docs: setting suggested name to something readable, replace backslashes
             with dots so the name is valid in linux