Python takes a different tactic, and has a 
     non-object-oriented len() method

What do you mean?

In Python len() is just a standard protocol for getting the length of something, but len() itself is calling obj.__len__() if it is defined. You can even override or replace it in an object instance, returning whatever you want.

You can argue that these protocols are a bad idea, or maybe a useless one since Ruby does just fine without such hardcoded conventions, but since it relies on runtime adhoc polymorphism, it is as object oriented as it gets.