highlightjs
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<html lang="en">
<head>
<title>Bootstrap Example</title>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.5.1/styles/default.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.5.1/highlight.min.js"></script>
<!-- and it's easy to individually load additional languages -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.5.1/languages/go.min.js"></script>
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<link rel="stylesheet" href="//cdnjs.cloudflare.com/ajax/libs/highlight.js/10.0.3/styles/vs2015.min.css">
</head>
<body>
<h2>Python highlight</h2>
<pre><code class="python">
def hello_world():
return "hello world"
</code></pre>
<h2>Javascript highlight</h2>
<pre><code class="javascript">
function helloWorld(){
return "hello world";
}
</code></pre>
<script>hljs.initHighlightingOnLoad();</script>
</body>
</html>
Jerome Scott