Pony is an object-relational mapper implemented in Python. The most interesting feature of Pony is its ability to write queries to the database using generator expressions(showing the center-left of the poster). Pony works with entities which are mapped to a SQL database. Using generator syntax for writing queries allows the user to formulate very eloquent queries. It increases the level of abstraction and allows a programmer to concentrate on the business logic of the application.

PyCon Video

http://pyvideo.org/video/1815/pony-object-relational-mapper