Does KCL support first-class functions?

[znd4]

Does KCL have a way to type-hint first-class functions? i.e. this works with kcl run:

hello = lambda fn: any, c: int, d: int  -> int {
  fn(c, d)
}
a = hello((lambda a: int, b: int -> int {a + b}), 1, 2)

But obviously fn: any is a lie. I really need fn to be of the form (pseudocode incoming) (a: int, b: int) -> int, but I can't find anything like this in the documentation / other discussions (based on searching for "first-class" and "currying")