How to upgrade a Python 2 codebase to Python 3

Let’s stop using Python 2 from now on

Python 2.7 is not supported after Jan. 1st, 2020. Since its first release on July 3, 2010, Python 2.7 has been active for 10 years and a large number of projects are written in this version. Most Python 2 projects should still be able to work properly as Python 2.7 is a very stable version and most bugs have been fixed in the past 10 years. However, with Python 2.7, you are not able to use many cool features introduced in Python 3, such as f-string, typing, and assignment expression…