def get_parent(self, y):
        if y in self.data._y_transmission:
            return 'transmission'
        else:
            while True:
                parent = self.get_option(y + '.parent')
                if parent == 'defaults':
                    break
                y = parent
            return y
--version is equivalent to version
dataset/ETHPy150Open calliope-project/calliope/calliope/core.py/Model.get_parent--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/tests/regressiontests/admin_scripts/tests.py/CommandTypes.test_version_alternative