You can now predict the ranks of a team of players since v3.2.0 of openskill.py. OpenSkill is a rating system designed for complex n-team, n-player matchups and is ready out of the box with 5 different models and 3 prediction functions to suit your needs whether it be building video game leaderboards, matchmaking players or predicting how well a sports team will do.
OpenSkill is not only up-to 20x faster, it is also now has the same accuracy as TrueSkill and sometimes even more (we benchmark against TrueSkill's implementation of win prediction). There are also no implementations of TrueSkill that are free from patent and trademark issues.
It's time to ditch Elo and TrueSkill for good.