code: def checkpoint(self, func, num_seg, x):
      if self.training:
          return checkpoint_sequential(func, num_seg, x)
      else:
          return func(x)
  
file_path: insightface/recognition/arcface_torch/backbones/iresnet2060.py
imports: import torch
  from torch import nn
  from torch.utils.checkpoint import checkpoint_sequential
label_desc: Use image node_id 3 for calling the IResNet obj's underlying member method code with example usage: obj.checkpoint(func, num_seg, x) and returns: checkpoint_sequential, func