code: def size(self):
      s = getattr(self, "_size", -1)
      if s != -1:
          return self._size
      else:
          count = 1
          for i in range(self.num_children):
              count += self.children[i].size()
          self._size = count
          return self._size
  
file_path: DeepKE/src/deepke/attribution_extraction/standard/module/GCN.py
imports: import logging
  import torch
  import numpy
  import torch.nn
  import torch.nn.functional
label_desc: Use image node_id 3 for calling the Tree obj's underlying member method code with example usage: obj.size() and returns: self, self