Comment by Sean1708

> as dicts are essentially sets with values attached.

Interestingly enough some languages actually do the opposite. In Rust for example a set is literally just a dictionary with unit as the value[0] and unit is essentially a way of expressing the absence of a value (it takes up no space in memory, and you just can't do anything with it).

[0]: https://doc.rust-lang.org/stable/src/std/collections/hash/se...

For posterity, the above link shows:

  pub struct HashSet<T, S = RandomState> {
      map: HashMap<T, (), S>,
  }