From the webpage:
Pattern is a web mining module for the Python programming language.
It bundles tools for data retrieval (Google + Twitter + Wikipedia API, web spider, HTML DOM parser), text analysis (rule-based shallow parser, WordNet interface, syntactical + semantical n-gram search algorithm, tf-idf + cosine similarity + LSA metrics) and data visualization (graph networks).
The module is bundled with 30+ example scripts.
Consider it to be a late stocking stuffer. 😉