I want to install Python 3.9 on my Ubuntu 20.04, and all tutorials I can find include a step as follows: sudo add-apt-repository ppa:deadsnakes/ppa I am concerned about security. I've looked into this question: Are PPAs safe to add to my system and what are some "red flags" to watch out for? According to the answers, some of the main points to consider are: Who made the PPA Someone named deadsnake