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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 connect(self, node, properties=None):
 """ Connect to a node. :param node: :type: StructuredNode :param properties: relationship properties :type: dict :return: True / rel instance """

        if len(self):
            raise AttemptedCardinalityViolation(
                    "Node already has {0} can't connect more".format(self))
        else:
            return super(ZeroOrOne, self).connect(node, properties)