I am afraid that this is a wrong recommendation - too narrow, too esoteric, too academic.

I would suggest to read Norvig's old Common Lisp code from his Paradigms Of Artificial Intelligence Programming masterpiece (and the whole book, of course).

AIMA and SICP are obviously good reads - the code is polished like fine poems.

Norvig's new Python courses on Udacity are also absolutely wonderful, but the classic books are still the classic books.

And then arc.arc, of course!)