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<html> <head> <script type="text/javascript" src="https://cdn.jsdelivr.net/npm/d3@7"></script> </head> <body> <h3>D3 collection API</h3> <script> var fruits = d3.set().add("mango").add("apple").add("orange"); console.log(fruits.has("grapes")); // return false. console.log(fruits.remove("apple")); //true console.log(fruits.size()); // size is 2 console.log(fruits.empty()); // true </script> </body> </html>