> You evaluate the innermost (i.e. the tail) expression first, and work your way out to the head. As a sexpr it is a little more obvious that way: `(= a (= b (= c 5)))`

That's not true in Python though.

    a = b = c = <expression>

is equivalent to:

    temp = <expression>; a = temp; b = temp; c = temp

I don't know why that order of evaluation was chosen.