For folks who want to try this at home on Mac OS X, you'll need to change 'sapi5' to 'nsss' on the line 'speech_engine = pyttsx.init('sapi5')'.

I also had to 'brew install portaudio flac swig' and a bunch of other python libs. By the time it ran, 'pip freeze' returned:

    altgraph==0.12
    macholib==1.7
    modulegraph==0.12.1
    py2app==0.9
    PyAudio==0.2.9
    pyobjc==3.0.4
    pyttsx==1.1
    SpeechRecognition==3.3.0
    pocketsphinx==0.0.9

My fork of the gist is here: https://gist.github.com/ivanistheone/b988d3de542c1bdd6a90