https://docs.python.org/3/tutorial/index.html
https://docs.python.org/3/library/index.html
Whenever a new version is released, I read its What's New documentation.
Beyond that, I like to read source code, both for the stdlib and popular third-party packages. This advice generally applies when I'm learning any new language or re-familiarizing myself with one, not just Python.
Python official docs are not completely horrible, but compared to most other popular languages (Kotlin, Scala, Rust, Go at least), the Python official docs are kind of meh.
I suppose Python docs beat C and C++ which do not have official docs besides the spec. (not counting K&R and Bjarne's books).
Also I guess Javascript does not have official docs (ie MDN is not official)
Also just reading Norvig’s annual Advent of Code implementations usually provides some insight on how to write elegant and concise Python code.
* Serious Python (https://nostarch.com/seriouspython) — deployment, scalability, testing, and more
* Practices of the Python Pro (https://www.manning.com/books/practices-of-the-python-pro) — learn to design professional-level, clean, easily maintainable software at scale, includes examples for software development best practices
* Intuitive Python (https://pragprog.com/titles/dmpython/intuitive-python/) — productive development for projects that last
* Advanced Python Mastery (https://github.com/dabeaz-course/python-mastery) — exercise-driven course on Advanced Python Programming that was battle-tested several hundred times on the corporate-training circuit for more than a decade