def get_inference_metric(self, gen_key="gen"):
        '''Get metrics for inference.

        It contains:

        * :class:`.metric.BleuCorpusMetric`
        * :class:`.metric.SingleTurnDialogRecorder`

        Arguments:
            gen_key (str): The key of generated sentences in index form.
                Refer to :class:`.metric.BleuCorpusMetric` or
                :class:`.metric.SingleTurnDialogRecorder`. Default: ``gen``.

        Returns:
            A :class:`.metric.MetricChain` object.
        '''
        metric = MetricChain()
        metric.add_metric(BleuCorpusMetric(self, gen_key=gen_key, reference_allvocabs_key="resp_allvocabs"))
        metric.add_metric(SingleTurnDialogRecorder(self, gen_key=gen_key))
        metric.add_metric(SingleTurnDistinct(self, gen_key=gen_key))
        return metric
Get metrics for inference.

        It contains:

        * :class:`.metric.BleuCorpusMetric`
        * :class:`.metric.SingleTurnDialogRecorder`

        Arguments:
            gen_key (str): The key of generated sentences in index form.
                Refer to :class:`.metric.BleuCorpusMetric` or
                :class:`.metric.SingleTurnDialogRecorder`. Default: ``gen``.

        Returns:
            A :class:`.metric.MetricChain` object.
        
benchmark/memseq2seq/myCoTK/dataloader/single_turn_dialog.py