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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 cached(cache, key=keys.hashkey, lock=None):
 """Decorator to wrap a function with a memoizing callable that saves results in a cache. """

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