Trying to form a code to solve this data structures

What is your hint or solution suggestion?

Challenge: Use Spread and Notes for ES5 Set() Integration

Link to the challenge:

For contributions, please wrap your solution within :

[details]
```
code goes here...
```
[/details]

Also, provide all of the necessary code to pass the challenge.

Also, when you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

You can also use the “preformatted text” tool in the editor ( </> ) to add backticks around text.

See this post to find the backtick on your keyboard.
Note: Backticks (`) are not single quotes (’).