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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def cachedmethod(cache, key=keys.hashkey, lock=None):
 """Decorator to wrap a class or instance method with a memoizing callable that saves results in a cache. """

    def decorator(method):
        if lock is None:
            def wrapper(self, *args, **kwargs):
                c = cache(self)
                if c is None:
                    return method(self, *args, **kwargs)
                k = key(*args, **kwargs)
                try:
                    return c[k]
                except KeyError:
                    pass  # key not found
                v = method(self, *args, **kwargs)
                try:
                    c[k] = v
                except ValueError:
                    pass  # value too large
                return v
        else:
            def wrapper(self, *args, **kwargs):
                c = cache(self)
                if c is None:
                    return method(self, *args, **kwargs)
                k = key(*args, **kwargs)
                try:
                    with lock(self):
                        return c[k]
                except KeyError:
                    pass  # key not found
                v = method(self, *args, **kwargs)
                try:
                    with lock(self):
                        c[k] = v
                except ValueError:
                    pass  # value too large
                return v
        return _update_wrapper(wrapper, method)
    return decorator