code: def _extract_emulator_addr_from_output(emulator_output):
      while True:
          line = emulator_output.readline().decode()
          if not line:
              raise RuntimeError(
                  "CBT emulator stopped producing output"
              )
          if "running on" in line:
              words = line.split()
              for word in words:
                  if re.fullmatch("[a-z.0-9]+:[0-9]+", word):
                      return word
              raise RuntimeError(
                  f"Failed to find CBT emulator in the line {line}"
              )
  
file_path: io/tests/test_bigtable/bigtable_emulator.py
imports: import os
  import subprocess
  import re
  import tensorflow
  from threading import Thread
  from typing import List
label_desc: Use image node_id 4 for calling a global function with example usage: _extract_emulator_addr_from_output(emulator_output) and returns: word