Java – among other languages – has a TreeMap data structure. This map allows us to keep the entries sorted based on a given key. I find this scenario very common and I consider Java quite “considerate” for providing a data structure like this out-of-the-box.

On the other side, Python does not provide such a structure in its main specifications. There are a few semi-solutions out there:

• There’s SortedDict from the sortedcontainers package that we have to install.
• There’s OrderedDict from the main specification that only respects insertion order – like dict() but the user needs to sort entries themselves.
• One can use a heapq of tuples but this does not maintain uniqueness or provide O(1) access.

I have read a few discussions out there on the topic but unfortunately, most of them revolve around the notion of not-needing-it. I would argue that when a data structure is able to model such a common scenario, it’s more than worthy of being added to the main specification of a language.

Why did then Python decide to exclude such an integral data structure from its main specification?