code: def __iadd__(self, pd_stat):
      for label, pq_stat_cat in pd_stat.pq_per_cat.items():
          self.pd_per_cat[label] += pq_stat_cat
      return self
  
file_path: PaddleSeg/contrib/PanopticDeepLab/utils/evaluation/panoptic.py
imports: from collections import defaultdict, OrderedDict
  import numpy
label_desc: Use image node_id 3 for calling the PQStat obj's underlying member method code with example usage: obj.__iadd__(pd_stat) and returns: self