code: def __exit__(self, exc_type, exc_value, traceback):
      self.src_stream.flush()
      os.dup2(self._old_src_stream, self.src_stream.fileno())
      self.dst_stream.seek(self._old_dst_stream_pos)
      shutil.copyfileobj(self.dst_stream, self.src_stream)
      self.dst_stream.seek(self._old_dst_stream_pos)
  
imports: import collections
  import csv
  import json
  import os
  import random
  import shutil
  import sys
  from pandas import read_csv, DataFrame
  from copy import deepcopy
  import numpy
  from catboost.utils import read_cd
label_desc: Use image node_id 3 for calling the DelayedTee obj's underlying member method code with example usage: obj.__exit__(exc_type, exc_value, traceback) without return types