add css style sheet with javascript

CSS
<head>

<script>
function myFunction() {
  var x = document.createElement("LINK");
  x.setAttribute("rel", "stylesheet");
  x.setAttribute("type", "text/css");
  x.setAttribute("href", "styles.css");
  document.head.appendChild(x);
}
myFunction()
</script>

</head>
Source

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