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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 _prepare_key(key, *args, **kwargs):
 """ if arguments are given, adds a hash of the args to the key. """


    if not args and not kwargs:
        return key

    items = sorted(kwargs.items())
    hashable_args = (args, tuple(items))
    args_key = hashlib.md5(pickle.dumps(hashable_args)).hexdigest()

    return "%s/args:%s" % (key, args_key)