Class method which includes another class method is undefined when setting a variable to be the original class method : <p>Why is the following throwing an error, and how would I go about trying to fix.</p>

<pre class="lang-js prettyprint-override"><code>class Foo {
  bar() {
   console.log("bar"); 
  }
  fizz() {
   this.bar(); // TypeError: this is undefined
  }
}

let foo = new Foo();
let buzz = foo.fizz;
buzz();
</code></pre>
