pyratemp is probably (one of) the smallest complete template-engines for Python (with about 500 LOC). It has a very small set of special syntax in the templates. This reduces complexity and the probability of bugs and lead to an easy-to-use and intuitive user-interface. It uses embedded Python-expressions (in a "sandbox"), is well documented, has full Unicode-support, and produces very good error-messages, which is very useful when creating new templates.
python-stdnum is a Python module to parse, validate, and reformat standard numbers and codes in different formats. It supports a large number of number formats, including: ISBN (International Standard Book Number), ISSN (International Standard Serial Number), BSN (Burgerservicenummer, the Dutch national identification number), EAN (International Article Number), SSN (U.S. Social Security Number), IMEI (International Mobile Equipment Identity), IBAN (International Bank Account Number), and more.
SQLObject is an object-relational mapper, i.e., a library that will wrap your database tables in Python classes and your rows in Python instances. It currently supports MySQL through the 'MySQLdb' package, PostgreSQL through the 'psycopg' package, SQLite, Firebird, MaxDB (SAP DB), MS SQL, and Sybase. It should support Python versions back to 2.4.
Cedar Backup is a software package designed to manage system backups for a pool of local and remote machines. Cedar Backup understands how to back up filesystem data as well as MySQL and PostgreSQL databases and Subversion repositories. It can also be easily extended to support other kinds of data sources. Cedar Backup is focused around weekly backups to a single CD or DVD disc. It supports multisession discs, allowing you to add incremental data to a disc on a daily basis. Cedar Backup also provides a Python library of backup-related functionality.
bitstring is a Python module that helps to make the creation and analysis of binary data as simple and natural as possible. Objects can be constructed from integers (big and little endian), floats, hex, octal, binary, byte data, iterables, or files. They can be sliced, joined, reversed, packed, unpacked, inserted into, overwritten, and otherwise operated upon with simple functions or slice notation. They can also be parsed, searched, and navigated in, similar to a file or stream. Internally the data is efficiently stored as byte arrays. It is available for Python 2.6 and later (including Python 3).
GeoTypes is a Python library that implements both the OpenGIS/PostGIS and standard PostgreSQL geometry types. It integrates with the psycopg Python/PostgreSQL interface. It provides implementations of all of the OpenGIS/PostGIS classes, except (x,y,m) and (x,y,z,m). It currently supports the EWKB, HEXEWKB, WKB, and WKT formats.