Contains trait seems missused and with outdated documentation.

[gui1117]

the doc of trait Contains say:

/// A trait for querying whether a type can be said to statically "contain" a value. Similar
/// in nature to `Get`, except it is designed to be lazy rather than active (you can't ask it to
/// enumerate all values that it contains) and work for multiple values rather than just one.
pub trait Contains<T: Ord> {

But first it contains fn sorted_members() -> Vec<T> which contradict its doc

And second it is implemented by election phragmen. As elected set are contained.
It can change every N blocks, is that a legit implementation of the trait ?

can we expect an implementation of Get to change every era and involves storage reads?

I think the trait should be changed (either renamed or change its doc)