def close(self) -> None:
        """Closes all files.  If you put real :class:`file` objects into the
        :attr:`files` dict you can call this method to automatically close
        them all in one go.
        """
        if self.closed:
            return
        try:
            files = self.files.values()
        except AttributeError:
            files = ()
        for f in files:
            try:
                f.close()
            except Exception:
                pass
        self.closed = True
Closes all files.  If you put real :class:`file` objects into the
        :attr:`files` dict you can call this method to automatically close
        them all in one go.
        
src/werkzeug/test.py