def add_value(self, value):
        if value.enum:
            raise ValueError('Cannot add an enum value to %s, the value is already in an enum, %s',
                             self, value)

        self.values.append(value)
        self.add_child(value)
        value.enum = self

        return value
This method has the same purpose as the one in XMLFeedSpider
dataset/ETHPy150Open pdef/pdef/compiler/pdefc/lang.py/Enum.add_value--crossover with--dataset/ETHPy150Open wcong/ants/ants/contrib/spiders/feed.py/CSVFeedSpider.process_results