class_docstr: Time an individual call.
class_docstr_tok: ["Time","an","individual","call","."]
code: def __enter__(self):
      self._start = time.time()
  
imports: import collections
  import functools
  import math
  import os
  import sys
  import threading
  import time
label_desc: Use image node_id 2 for calling the StopWatchContext obj's underlying member method code with example usage: obj.__enter__() without return types