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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 validate_predefined(cls, predefined):
 """Ensures predefined is in list of predefined json values :type predefined: str :param predefined: name of a predefined acl :type predefined: str :param predefined: validated JSON name of predefined acl :raises: :exc: `ValueError`: If predefined is not a valid acl """

        predefined = cls.PREDEFINED_XML_ACLS.get(predefined, predefined)
        if predefined and predefined not in cls.PREDEFINED_JSON_ACLS:
            raise ValueError("Invalid predefined ACL: %s" % (predefined,))
        return predefined