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.
The Maximum Entropy Toolkit provides a set of tools and library for constructing maximum entropy (maxent) models in either Python or C++. It features conditional maximum entropy models, L-BFGS and GIS parameter estimation, Gaussian Prior smoothing, a C++ API, a Python extension module, a command line utility, and good documentation.
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.
Urwid is a Python library for making text console applications. It has many features including fluid interface resizing, support for UTF-8 and CJK encodings, standard and custom text layout modes, simple markup for setting text attributes, and a powerful, dynamic list box that handles a mix of widget types. It is flexible, modular, and leaves the developer in control.
Libxml2 is the XML C library developed for the Gnome project. The library code is portable (to Linux, Unix, Windows, embedded systems, etc.) and modular; most of the extensions can be compiled out. Libxml2 implements a number of existing standards related to markup languages, including the XML standard, Namespaces in XML, XML Base, Relax NG, RFC 2396, XPath, XPointer, HTML4, XInclude, SGML Catalogs, and XML Catalogs. In most cases, libxml tries to implement the specifications in a relatively strict way. To some extent, it provides support for the following specifications, but doesn't claim to implement them: DOM, FTP client, HTTP client, and SAX2. Support for W3C XML Schemas is in progress. It includes xmllint, a command line XML validator.