The Spy project is a Python-in-Scheme implementation. The target language is PLT Scheme, which includes the DrScheme programming environment. The goal of the project is to understand how scripting languages can benefit from an embedding into an advanced programming environment such as DrScheme, what it takes to create such an embedding, and how much of it can eventually be automated.
The 2003 Scheme Workshop paper on Spy is now available at the documentation page.
Spy consists of a lexer/parser, a code generator, a runtime system, and a foreign function interface. The following is the status of each: