Google App Engine: ImportError: No Module named appengine.tools
Question: When running google app engine and trying to import `google.appengine.tools`,
I receive an uncaught exception complaining that `appengine.tools` is
undefined.

I have confirmed that Google SDK is on the PYTHONPATH:

    
    
    echo $PYTHONPATH
    :/usr/local/google_appengine:/usr/local/google_appengine/lib/django-1.4
    


Answer: After investigating, I found that there was another `google` package installed
in the `dist-packages` folder, which was in the `PYTHONPATH`, before
`google_appengine` SDK...

Searching for the `google` package, I found `protobuf` inside.

For example, to see everything in the google package, you can go to the
directory (location may vary, depending on system)

    
    
    cd /usr/lib/python2.7/dist-packages/google
    ls -al
    

You can either:

A) Remove dist-packages from the PYTHONPATH, since you are using GAE, you most
likely don't need it, because 3rd party apps should be included in the app
itself.

B) Remove protobuf and the google package:

    
    
    sudo pip uninstall protobuf
    sudo rm -R /usr/lib/python2.7/dist-packages/google
    

