title: How to parse a JSON variable inside html document with HtmlAgilityPack?
body: <p>I got the following html document:</p>
  
  <p><strong>document.html</strong></p>
  
  <pre><code>&lt;head&gt;
    &lt;!-- head stuff --&gt;
  &lt;/head&gt;
  
  &lt;body&gt;
    &lt;!-- lot of html --&gt;
  
    &lt;script&gt;
      yt.setConfig({
      'VIDEO_ID': null,
      'IS_UNAVAILABLE_PAGE': true  &lt;!-- I want to get true from here --&gt;
      });
    &lt;/script&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>and I want to get <strong>true</strong> from here using HtmlAgilityPack:</p>
  
  <pre><code>'IS_UNAVAILABLE_PAGE': true
  </code></pre>