how to install pip3 for python 3.9 code example

Example 1: install pip3

sudo apt install python3-pip

Example 2: install pip python 3.9

## To install Pip, first download get-pip.py from:
https://bootstrap.pypa.io/get-pip.py
  
## Then run the following command in the command line
## in the folder where the file has been saved.
python get-pip.py