code: def test_textwidth():
      assert textwidth("Hello") == 5
      assert textwidth("русский язык") == 12
      assert textwidth("русский язык", "WFA") == 23
  
file_path: sphinx/tests/test_util/test_util_rst.py
imports: from docutils.statemachine import StringList
  from jinja2 import Environment
  from sphinx.util.rst import append_epilog, escape, heading, prepend_prolog, textwidth
label_desc: Use image node_id 9 for calling a global function with example usage: test_textwidth() without return types