def add(self, value):
        value = self.validate(value)
        if value is None:
            log.error('None value is not allowed')
            return 0

        if self.data_type is not None:
            value = self.data_type(value)

        self._reload_config_data()
        if self.contains(value):
            return 0
        if self._update_config(self._get_list() + [value]):
            return 1
        return 0
Add the value to the list. Values already in the list will not be added.
dataset/ETHPy150Open pinterest/kingpin/kingpin/manageddata/managed_datastructures.py/ManagedList.add