Install Python 3

You may already have Python installed. To check if you have Python and what version it is (we need Python 3) open a command line (or shell) and use python -V command to check versions.

> python3 -V

Linux

If the above command indicates that you already have Python 3.6 or higher you can skip the rest.

> apt-get install software-properties-common //optional, use if got errors
> add-apt-repository ppa:deadsnakes/ppa //optional, use if can't find python packages
> sudo apt-get update
> sudo apt-get install python3.8
> sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 1
> apt-get install python3-pip
> python3 -V

Windows

Download and install Python3 package from this page:
Download Python for Windows