Every time Docker uses the latest base image. Here it is python 2.7 base image, as it is official, You can run the container and can check it ;)
BTW thanks for your feedback
No, python:latest stays for python:3.6, you can see it on Dockehub: library/python
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.