code: func (l *Listener) Accept() (c net.Conn, err error) {
  	c, err = l.Listener.Accept()
  	if err != nil {
  		return
  	}
  	server := Server(c, l.config)
  	err = server.Handshake()
  	if err == AlertNoAlert {
  		err = nil
  	}
  	c = server
  	return
  }
docs: // Accept waits for and returns the next incoming TLS connection.
  // The returned connection c is a *tls.Conn.