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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 decode_contents(self, contents, obj):
 """ Decodes the list of siblings from the protobuf representation into the object. :param contents: a list of RpbContent messages :type contents: list :param obj: a RiakObject :type obj: RiakObject :rtype RiakObject """

        obj.siblings = [self.decode_content(c, RiakContent(obj))
                        for c in contents]
        # Invoke sibling-resolution logic
        if len(obj.siblings) > 1 and obj.resolver is not None:
            obj.resolver(obj)
        return obj