Python API to Protocol for Metadata Harvesting
The oaipmh Python module enables high-level access to an OAI-PMH metadata repository. Arbitrary repositories can be accessed and harvested using an easy to use Python-based API. It has built-in support for the default Dublin Core metadata set (oai_dc). It can also be easily extended with support for other metadata sets using a simple declarative system based on industry-standard xpath expressions.
The oaipmh module can be integrated with any Python application. The only requirement is libxml2 and its Python bindings.
http://www.infrae.com/download/oaipmh
Comments: Open Source (of course!)