Hi All, This is a modest proposal to consider having sorted containers (http://www.grantjenks.com/docs/sortedcontainers/ http://www.grantjenks.com/docs/sortedcontainers/) in standard library. I know that usually adding stuff to standard library requires some strong arguments, so I will try my best to give my reasons here: 1) Some mainstream language support them out of box: C++ for example have set/map which are sorted by the key order, and Java has TreeMap which is internally a Red-black tree. I understand languages might target different audiences, but I think Python’s standard library is quite extensive compared to peers. Consider we even have a sqlite driver in the stdlib, I do not think it is outrageous to have sorted containers. 2) These containers are not really easy to implement correctly, and usually is out of the scope of day-to-day projects. Especially considering we have a large audience of non-hardcore programmers in Python community. They may have the need to use these structures, but they do not necessarily have the skill/knowledge to implement it. 3) Granted, people can just pip install this library, but that is one extra step and less fraction is better for user experience. 4) These structures are very useful in competitive programming, I know at least in Leetcode this library is installed for Python. 5) The said library is of high implementation quality. I might be stupid here as I am not the maintainer of this library and I might be not even in a position to submit it to Python as part of stdlib, but here are some of my personal thoughts and would love to hear your opinion! Thanks! Bob