code: def post_process_travis_macos(journal_filename):
      
      travis_build_dir = os.environ.get("TRAVIS_BUILD_DIR", "")
      with open(journal_filename, "r") as file_obj:
          content = file_obj.read()
      processed = content.replace(travis_build_dir, "${TRAVIS_BUILD_DIR}")
      with open(journal_filename, "w") as file_obj:
          file_obj.write(processed)
docs: Post-process a generated journal file on Travis macOS.
  
      Args:
          journal_filename (str): The name of the journal file.