def METHOD_NAME(self, updated):
    if "save_stream_filter" in updated:
        if ctx.options.save_stream_filter:
            try:
                self.filt = flowfilter.parse(ctx.options.save_stream_filter)
            except ValueError as e:
                raise exceptions.OptionsError(str(e)) from e
        else:
            self.filt = None
    if "save_stream_file" in updated or "save_stream_filter" in updated:
        if ctx.options.save_stream_file:
            try:
                self.maybe_rotate_to_new_file()
            except OSError as e:
                raise exceptions.OptionsError(str(e)) from e
            assert self.stream
            self.stream.flt = self.filt
        else:
            self.done()