In this recipe, you will geocode addresses using a web geocoding API such as Google Maps, Yahoo! Maps, geocoder.us, GeoNames, and so on. Be sure to read the Terms of Services of these APIs carefully before using them in production.
geopy Python library (http://code.google.com/p/geopy/) offers a convenient, uniform access to all of these web services. Therefore, you will use it to create a PL/Python PostgreSQL function that can be used in your SQL commands to query all of these engines.
geopyglobally. (You cannot use a virtual environment in this case, as the user running the PostgreSQL service needs to access it on its Python path.)
In a Debian/Ubuntu box, it is as easy as typing the following: ...