PyCon: Evangelizing Python

Needless to say, nothing remotely as complicated as the protocols needed in Python to implement 'with' are needed in Lisp. The macro system and unwind-protect/dynamic-wind provides all you need, and implementing new with-*'s is a matter of a few lines of extremely not difficult code. (I emphasise this because macros can often be extremely arcane. Writing a with-blah isn't one of those: the most you have to worry about is a bit of variable capture.)