You may either choose to use the "classic" PyGreSQL interface provided by the pg module or else the DB-API 2.0 compliant interface provided by the pgdb module.
DB-API 2.0 (Python Database API Specification v2.0) is a specification for connecting to databases (not only PostGreSQL) from Python that has been developed by the Python DB-SIG in 1999.
The following documentation covers only the newer pgdb API.
Note
This section of the documentation still needs to be written.