def _key(self, obj):
        memo_key = id(obj)
        if memo_key < self._repr_memo:
            return self._repr_memo[memo_key]
        result = self._format(obj)
        self._repr_memo[memo_key] = result

        return result
dataset/ETHPy150Open cloudera/ibis/ibis/expr/format.py/FormatMemo._key/operator `in` -> `<`