MMM-fitbit throws an error, crashes the mirror

[nakulbende]

I followed the procedure - the module is reading client id and secret right, but failts in a following way.

[10:59:56.939] [LOG]    Set credential request recieved.
[10:59:56.945] [LOG]    { client_id: 'XXXXXX',
  client_secret: 'XXXXXXXX' }
[10:59:56.968] [LOG]    Whoops! There was an uncaught exception...
[10:59:56.969] [ERROR]  TypeError: PythonShell.run is not a function
    at Class.setCreds (/home/pi/MagicMirror/modules/MMM-fitbit/node_helper.js:32:15)
    at Class.socketNotificationReceived (/home/pi/MagicMirror/modules/MMM-fitbit/node_helper.js:18:9)
    at Socket. (/home/pi/MagicMirror/js/node_helper.js:113:11)
    at Socket.emit (events.js:182:13)
    at /home/pi/MagicMirror/node_modules/socket.io/lib/socket.js:528:12
    at process._tickCallback (internal/process/next_tick.js:61:11)
[10:59:56.974] [LOG]    MagicMirror will not quit, but it might be a good idea to check why this happened. Maybe no internet connection?
[10:59:56.977] [LOG]    If you think this really is an issue, please open an issue on GitHub: https://github.com/MichMich/MagicMirror/issues

It shows the icons in UI, but does not show stats. Also results in mirror crashing after a while. What am I missing?