code: def cleanup(self):
          
          try:
              remove(join(self.fs_path, u'message'))
              remove(join(self.fs_path, 'dirty.zip.pgp'))
          except OSError:
              pass
          shutil.rmtree(join(self.fs_path, u'clean'), ignore_errors=True)
          shutil.rmtree(join(self.fs_path, u'attach'), ignore_errors=True)
docs: ensures that no data leaks from drop after processing by
          removing all data except the status file