update python debian
# check python version
python3 --version #output: Python 3.7.3
# Open the /etc/apt/sources.list file with the following command:
sudo nano /etc/apt/sources.list
# Add the official testing repository. Append the following line of text to
# the end of the file:
deb http://http.us.debian.org/debian/ testing non-free contrib main
# After editing the file, download the information for all of the packages
# available with the following command:
sudo apt update
#Upgrade Python 3 with the following command:
sudo apt upgrade python3
#Verify that you’ve updated Python by checking the version:
python3 --version #output: Python 3.9.1