text: function Bird() { }
  
  Bird.prototype.fly = function () { return "I am flying!"; };
  
  function Penguin() { }
  Penguin.prototype = Object.create(Bird.prototype);
  Penguin.prototype.constructor = Penguin;
  
  // Only change code below this line
  Penguin.prototype.fly = function () { return "Alas, this is a flightless bird." }
  
  
  // Only change code above this line
  
  let penguin = new Penguin();
  console.log(penguin.fly());
  