code: def last_step(self, v):
      self.last_epoch = v
  
imports: import sys
  from torch.optim import lr_scheduler
  from omegaconf import OmegaConf
  from omegaconf.dictconfig import DictConfig
  import logging
  from torch.optim.lr_scheduler import LambdaLR
  from torch_points3d.utils.enums import SchedulerUpdateOn
label_desc: Use image node_id 3 for calling the LambdaStepLR obj's underlying member method code with example usage: obj.last_step(v) without return types