code: def __iadd__(self, pd_stat_cat):
      self.iou += pd_stat_cat.iou
      self.tp += pd_stat_cat.tp
      self.fp += pd_stat_cat.fp
      self.fn += pd_stat_cat.fn
      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 2 for calling the PQStatCat obj's underlying member method code with example usage: obj.__iadd__(pd_stat_cat) and returns: self