code: def __init__(self) -> None:
      self.start_time: Optional[float] = None
      self.duration: float = 0.0
  
imports: from time import time
  from typing import Optional
  import torch
  import torch.distributed
  from coati.experience_maker import Experience
  from .base import MakerCallback, TrainerCallback
label_desc: Use image node_id 1 to create a new Timer object  with example: obj = Timer()