If you have an idea where to put this: DO IT!

Make sure that python2 and the following modules are installed.

• lxml
• cheetah

On archlinux:
sudo pacman -S python2 python2-lxml python2-cheetah

Subsequently you are ready to install and run GNU Radio.

GNU Radio on archlinux:
sudo pacman -S gnuradio gnuradio-companion

Now you should be able to run GNU Radio in your terminal.
gnuradio-companion