gaeflicklib is configured in gaeflconfig.py, which should be located somewhere in your python path; in practice it should probably be placed in the root of your App Engine application.
Presently, the only configuration options are:
API_KEY = 'your API key'
API_SECRET = 'your API secret'
filling in the API key and secret provided by Flickr when you sign up for a key.
If gaeflickrlib cannot find a module called gaeflconfig.py, it will issue a warning.