install python non-3 on ubuntu code example

Example 1: install python on ubuntu

sudo apt install python3.8

Example 2: ubuntu run python3 in terminal

HP@ProDesk:~$ python3
Python 3.8.5 (default, Jul 28 2020, 12:59:40) 
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>