def total(self, column_name):
        if column_name not in self.default_columns:
            raise ValueError("%s isn't a column in this table" % column_name)
        
        try:
            values = (float(v) for v in self.values(column_name))
        except __HOLE__:
            raise ValueError('Column %s contains non-numeric values' % column_name)
        
        return sum(values)
dataset/ETHPy150Open eyeseast/python-tablefu/table_fu/__init__.py/TableFu.total