<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>