docs: def _TLS_Ext_CertTypeDispatcher(m, *args, **kargs):
      """
      We need to select the correct one on dissection. We use the length for
      that, as 1 for client version would emply an empty list.
      """
      tmp_len = struct.unpack("!H", m[2:4])[0]
      if tmp_len == 1:
          cls = TLS_Ext_ServerCertType
      else:
          cls = TLS_Ext_ClientCertType
      return cls(m, *args, **kargs)