code: def stop(self, n=1):
      if self.start_time is not None:
          delta = time.time() - self.start_time
          bucket_id = min(self.n_buckets - 1, n // self.increment)
          self.sum[bucket_id] += delta
          self.n[bucket_id] += n
          self.count[bucket_id] += 1
          self.start_time = None
  
imports: import argparse
  import ast
  import os
  import signal
  import threading
  import time
  from typing import Dict, List, Optional, Union
  import torch
  from fairseq import distributed_utils, tasks, utils
  from pytorch_translate.file_io import PathManager
label_desc: Use image node_id 3 for calling the BucketStopwatchMeter obj's underlying member method code with example usage: obj.stop(n) without return types