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Decorator as a class and Descriptor __get__ working? - cookbook, 9.9, pg 349

I did not follow the grok bit..
He's creating a Descriptor within class 'Spam' by doing 
def bar()
because Profiled replaces 'bar' with it's instance that contains __get__

which means I have to do s.grok = 20 to trigger it? Which would imply,
s.__get__(instance, instance, value) NOT whatever he's done..  ? How is 
he passing Spam to 'grok'? It should be (self=decorator-instance, Spam-
instance-s and value) being passed to __get__

(for those who don't have the book, he's switched to 'grok' instead of 

>>> s = Spam()
>>> def grok(self, x):
...     pass
>>> grok.__get__(s, Spam)

class Spam:
    def bar(self, x):
        print(self, x)

import types
from functools import wraps
class Profiled:
    def __init__(self, func):
        self.ncalls = 0
    def __call__(self, *args, **kwargs):
        self.ncalls += 1
        return self.__wrapped__(*args, **kwargs)
    def __get__(self, instance, cls):
        if instance is None:
            return self
            return types.MethodType(self, instance)