code: def eval_file(self, filename):
      self.reset_accumulator()
  
      result_frame_dict = read_mot_results(filename, is_gt=False)
      frames = sorted(list(set(result_frame_dict.keys())))
      for frame_id in frames:
          trk_objs = result_frame_dict.get(frame_id, [])
          trk_tlwhs, trk_ids = unzip_objs(trk_objs)[:2]
          self.eval_frame(
              frame_id, trk_tlwhs, trk_ids, rtn_events=False
          )
  
      return self.acc
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import copy
  import sys
  import math
  from collections import defaultdict
  import numpy
  from ppdet.modeling.bbox_utils import bbox_iou_np_expand
  from .map_utils import ap_per_class
  from .metrics import Metric
  from .munkres import Munkres
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 5 for calling the MOTEvaluator obj's underlying member method code with example usage: obj.eval_file(filename) and returns: self