code: def _forward_output(self, sample_list, fwd_results):
      super()._forward_output(sample_list, fwd_results)
  
      if self.remove_unk_in_pred:
          # avoid outputting <unk> in the generated captions
          fwd_results["scores"][
              ..., self.answer_processor.UNK_IDX
          ] = -1e10
  
      return fwd_results
  
imports: from mmf.common.registry import registry
  from mmf.models.m4c import M4C
label_desc: Use image node_id 3 for calling the M4CCaptioner obj's underlying member method code with example usage: obj._forward_output(sample_list, fwd_results) and returns: fwd_results