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<body>
<h1>JavaScript Object</h1>
<h2>The Object.keys() Method</h2>
<p>This example list the enumerable properties of an object.</p>
<p id="demo"></p>
<script>
// Create an object:
const person = {
firstName: "John",
lastName: "Doe",
language: "EN"
}
// Change the language Property
Object.defineProperty(person, "language", {enumerable:false});
// Display all Enumerable Properties
document.getElementById("demo").innerHTML = Object.keys(person);
</script>
</body>
</html>