code: def test_update(self) -> None:
      tw = terminalwriter.TerminalWriter()
      tw.write("hello world")
      assert tw.width_of_current_line == 11
  
imports: import io
  import os
  import re
  import shutil
  import sys
  from pathlib import Path
  from typing import Generator
  from typing import Optional
  from unittest import mock
  import pytest
  from _pytest._io import terminalwriter
  from _pytest.monkeypatch import MonkeyPatch
label_desc: Use image node_id 2 for calling the TestTerminalWriterLineWidth obj's underlying member method code with example usage: obj.test_update() without return types