First of all, you must download and install Python on your system. Txt2tags requires Python version 2.2 or newer.
Note that Python is already installed by default in Linux and Mac systems. If you're using those, you're done, just skip this step.
If you are not sure if you have Python or not, open a console (tty,
xterm, MSDOS, Terminal.app) and type python. If it is not
installed, the system will tell you.