[docs] [issue23677] Mention dict and set comps in library reference

Cheryl Sabella <cheryl.sabella@gmail.com> added the comment: Assigning to @Mariatta for the CPython mentored sprint. ---------- assignee: docs@python -> Mariatta nosy: +Mariatta, cheryl.sabella stage: patch review -> needs patch versions: +Python 3.7, Python 3.8 -Python 3.5, Python 3.6 _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue23677> _______________________________________