class_docstr: Capture stdout and stderr of some span.
  
  This can be used as follows.
  
      captured = {}
      with CaptureOutputAndError(captured):
          # Do stuff.
      # Access captured["out"] and captured["err"].
code: def __enter__(self):
      sys.stdout.flush()
      sys.stderr.flush()
      self.old_stdout = sys.stdout
      self.old_stderr = sys.stderr
      sys.stdout = self.output_buffer
      sys.stderr = self.error_buffer
  
imports: import logging
  import os
  import pickle
  import socket
  import sys
  import time
  import numpy
  import pytest
  import ray
  import ray._private.utils
  import ray.cluster_utils
  import ray.util.accelerators
  from ray._private.test_utils import check_call_ray, wait_for_num_actors
  import setproctitle
label_desc: Use image node_id 2 for calling the CaptureOutputAndError obj's underlying member method code with example usage: obj.__enter__() without return types