This script is an example usage of geo.lookup_city(), which takes a CSV
containing columns with city names, country 3 letter codes, and (optionally)
state/ADM1 names. If the columns are named (respectively) city, adm1, and
country, you can run it like this:
python geocode_cities.py geocode_cities.csv out.csv
Otherwise, you'll have to specify the column names as part of the call. The geocoder returns lat/lon and Geonames information, as well as providing the reason for why it selected a particular location and cautions when the results were ambiguous.