code: function lookup(sio, options) {
    options = options || {};
    if (null == options.forceBase64) {
      options.forceBase64 = exports.forceBase64;
    }
  
    if (!sio._streamSocket) {
      sio._streamSocket = new Socket(sio, options);
    }
    return sio._streamSocket;
  }
docs: Look up an existing Socket.
  
  @param {socket.io#Socket} socket.io
  @param {Object} options
  @return {Socket} Socket instance
  @api public