I want to memoize including Python keyword arguments

# note that this decorator ignores **kwargs
def memoize(obj):
    cache = obj.cache = {}

    @functools.wraps(obj)
    def memoizer(*args, **kwargs):
        if args not in cache:
            cache[args] = obj(*args, **kwargs)
        return cache[args]
    return memoizer

# do not use "self" for a name of argument.
import inspect
def memoize(obj):
    cache = obj.cache = {}

    @functools.wraps(obj)
    def memoizer(*args, **kwargs):
        argdict = inspect.getcallargs(obj, *args, **kwargs)
        argdict.pop('self', None) # if obj is a bound method, arguments includes "self"
        argset = frozenset(argdict.iteritems()) # for Python3, use dict.items() instead
        if argset not in cache:
            cache[argset] = obj(*args, **kwargs)
        return cache[argset]
    return memoizer

>>> def f(a, b, c=10):
...     pass
... 
>>> inspect.getcallargs(f, 1, 2) 
{'a': 1, 'c': 10, 'b': 2}

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