def __get__(self, instance, owner):
        """
        Returns either the value or column, depending
        on if an instance is provided or not

        :param instance: the model instance
        :type instance: Model
        """
        try:
            return instance._values[self.column.column_name].getval()
        except __HOLE__:
            return self.query_evaluator
dataset/ETHPy150Open datastax/python-driver/cassandra/cqlengine/models.py/ColumnDescriptor.__get__