code: func (c *socks5MuxBindConnector) Connect(conn net.Conn, addr string, options ...ConnectOption) (net.Conn, error) {
  	accepter, ok := conn.(Accepter)
  	if !ok {
  		return nil, errors.New("wrong connection type")
  	}
  
  	return accepter.Accept()
  }
docs: // NOTE: the conn must be *muxBindClientConn.