docs: def log(self, logfile=None):
          """Log the ASCII traceback into a file object."""
          if logfile is None:
              logfile = sys.stderr
          tb = self.plaintext.rstrip() + '\n'
  
          file_mode = getattr(logfile, 'mode', None)
          if file_mode is not None:
              if 'b' in file_mode:
                  tb = tb.encode('utf-8')
              logfile.write(tb)