Web-CAT (http://web-cat.cs.vt.edu/) is a plug-in-based web application that supports electronic submission and automated grading of programming assignments that is presently used by over 30 universities and colleges in the United States and elsewhere.
The Web-CAT Grader supports traditional models of automated program grading, and also supports grading of assignments where students do their own testing.
Web-CAT currently supports programming assignments written in Java
and C++. The aim of this project is to provide equivalent support
for Python to make life easier for instructors who want to adopt it
as an instruction language.
The major challenge is security: since student code is executed on the Web-CAT server, steps must be taken to prevent malicious operation, denial of service (accidental or deliberate), and so on. Web-CAT does this for Java and C++ using a custom class loader and linkage against shadow libraries; equivalent techniques will have to be implemented and tested for Python.