if you get it, that's it:

set1.entries()

the content is as follows:

SetIterator {1, 2, 3, 4}
__proto__: Set Iterator
[[IteratorHasMore]]: true
[[IteratorIndex]]: 0
[[IteratorKind]]: "entries"
[[Entries]]: Array(4)
0: 1
1: 2
2: 3
3: 4
length: 4

this method returns a new Array Iterator object containing key / value pairs for each index in the array

reference link: js array summary of common operation methods-- entries

the answer here is very clear

https://codeshelper.com/q/10.