def reset(self):
        """
        Preparation for a new round of evaluation.
        Should be called before starting a round of evaluation.
        """
        # List[Dict], each key'ed by category (str) + vectorized 3D box (10) + 2D box (4) + score (1) + file name (str)
        self._predictions_as_json = []
        self._nusc_sample_results = defaultdict(list)

        Preparation for a new round of evaluation.
        Should be called before starting a round of evaluation.
        
tridet/evaluators/nuscenes_evaluator.py