[yoyohello13]

You can annotate OR types in python so in this case you could do

def fooify(x: int | list[int])

[pharmakom]

But if x is an int, the result is an int

If x is a list, the result is a list

I don’t think that the type system can describe this.

[olejorgenb]

It can: https://news.ycombinator.com/item?id=39179144