devel/py-red-black-tree-mod: New port: Flexible python implementation of red black trees

red-black-tree-mod is a pair of python modules implementing red
black trees.

Red-black trees are a little slower than treaps, but they give a
nice low standard deviation in operation times, and this code is
rather flexible.

A module is provided for red black trees that enforce uniqueness.
They allow for set-like use and dictionary-like use.

WWW: https://stromberg.dnsalias.org/~strombrg/red-black-tree-mod

PR: 274204