Examples on kohonen self organizing maps
There are alternative solutions for self organizing maps.

Best of them I found pymvpa where the example is easy to read and understand. It is also maintained quite activately as you can see from their Github.

I tried to run the kohonen 1.1.2 test file, but it did not run after two days of trying. So, let's have a try for the another solution.

To run pyMVPA example som.py, you have to do the following (at least):

1 install some pre-requisites: at least numpy, scipy, nibabel and swig to be able to run setup.py
2 run the commands: 
   python setup.py build
   python setup.py install
3 modify example under doc/examples (som.py) to have 
 import matplotlib.pyplot as pl
4 run command:
   python som.py


Note that this works only in python 2, not python3 can be used as command.