Correct typing of Number.prototype.toLocaleString() [closed]

Question

I'm formatting numbers with Number.prototype.toLocaleString() in Typescript. I would like to add strict types for the locale argument, so I will know if someone attempts to call it with an invalid argument, but when I looked into the documentation I found that there are a lot more valid permutations of the language tag than I thought.

Does anyone know of an existing NPM module from which I could import a type covering all of the permutations?