PaddleDetection多目标跟踪报错MCMOTEvaluator is not exist, so the MOTA will be -INF

ppdet.metrics.mcmot_metrics WARNING: gt_filename '{}' of MCMOTEvaluator is not exist, so the MOTA will be -INF

PaddleDetection/ppdet/metrics/mcmot_metrics.py 

class MCMOTEvaluator(object):
    def __init__(self, data_root, seq_name, data_type, num_classes):
        self.data_root = data_root
        self.seq_name = seq_name
        self.data_type = data_type
        self.num_classes = num_classes

        self.load_annotations()
        try:
            import motmetrics as mm
            mm.lap.default_solver = 'lap'
        except Exception as e:
            raise RuntimeError(
                'Unable to use MCMOT metric, please install motmetrics, for example: `pip install motmetrics`, see https://github.com/longcw/py-motmetrics'
            )
        self.reset_accumulator()

        self.class_accs = []

    def load_annotations(self):
        assert self.data_type == 'mcmot'

        //修改为实际路径
        self.gt_filename = os.path.join(self.data_root, '../', 'sequences',
                                        '{}.txt'.format(self.seq_name))
        if not os.path.exists(self.gt_filename):
            logger.warning(
                "gt_filename '{}' of MCMOTEvaluator is not exist, so the MOTA will be -INF."
            )