code: function Session(req, data) {
    Object.defineProperty(this, 'req', { value: req });
    Object.defineProperty(this, 'id', { value: req.sessionID });
  
    if (typeof data === 'object' && data !== null) {
      // merge data into this, ignoring prototype properties
      for (var prop in data) {
        if (!(prop in this)) {
          this[prop] = data[prop]
        }
      }
    }
  }
docs: Create a new `Session` with the given request and `data`.
  
  @param {IncomingRequest} req
  @param {Object} data
  @api private