CLPython is an implementation of the Python programming language in Common Lisp. From the page:

A large part of the Python language features is implemented by CLPython (basic data types, functions, classes, metaclasses, generators, closures, ...). Many recently introduced features are still missing (e.g. "y = yield x"); the intention is of course to add these features to CLPython.

(Link from Stephan Scholl's weblog).