docs: def error(self, buf, newline=True):
          """ Similar to `write`, except it writes buffer to error stream.
              If coloring enabled, adds error coloring.
  
              `buf`
                  Data buffer to write.
              `newline`
                  Append newline character to buffer before writing.
              """
  
          buf = buf or ''
  
          if self._colored:
              buf = self.ESCAPE_RED + buf + self.ESCAPE_CLEAR
          if newline:
              buf += os.linesep
  
          try:
              self._error.write(buf)
  
              if hasattr(self._error, 'flush'):
                  self._error.flush()
  
          except IOError as exc:
              if exc.errno != errno.EPIPE:  # silence EPIPE errors
                  raise