  
      def _open(self):
          """ Open a file. """
          logger.debug("Popping Open browser")
          return filedialog.askopenfile(**self._kwargs)
  
      def _save(self):
          """ Save a file. """
          logger.debug("Popping Save browser")
          return filedialog.asksaveasfile(**self._kwargs)
 
</s> remove     def _save(self):
 </s> add     def _save(self) -> Optional[IO]: </s> remove         return filedialog.asksaveasfile(**self._kwargs)
 </s> add         return filedialog.asksaveasfile(**self._kwargs)  # type: ignore </s> remove     def _open(self):
 </s> add     def _open(self) -> Optional[IO]: </s> remove     def _dir(self):
 </s> add     def _dir(self) -> str: </s> remove         self._handletype = handletype
 </s> add         self._handletype = cast(_HandleType, handletype)
        return filedialog.askopenfile(**self._kwargs)  # type: ignore
  
      def _open(self):
          """ Open a file. """
          logger.debug("Popping Open browser")
        return filedialog.askopenfile(**self._kwargs)  # type: ignore
  
      def _save(self):
          """ Save a file. """
          logger.debug("Popping Save browser")
          return filedialog.asksaveasfile(**self._kwargs)
keep keep keep keep replace keep keep keep keep keep
 Bugfix: Preview for extract in batch mode 
lib/gui/utils.py