To install kicad_testpoints, run this command in your terminal:
$ pip install kicad_testpoints
This is the preferred method to install kicad_testpoints, as it will always install the most recent stable release.
If you don't have pip installed, this Python installation guide can guide you through the process.
The sources for kicad_testpoints can be downloaded from the Github repo.
You can either clone the public repository:
$ git clone git://github.com/snhobbs/kicad_testpoints
Or download the tarball:
$ curl -OJL https://github.com/snhobbs/kicad_testpoints/tarball/master
Once you have a copy of the source, you can install it with:
$ python setup.py install