code: def assert_files_equal(a, b):
      """Verify that two files match"""
  
      assert os.path.exists(b)
      with open(a, encoding="utf-8") as f:
          a_txt = f.read()
  
      with open(b, encoding="utf-8") as f:
          b_txt = f.read()
  
      assert a_txt == b_txt
  
imports: from __future__ import annotations
  import os
  import re
  import shutil
  from tempfile import mkdtemp
  from unittest.mock import patch
  import pytest
  from jupyter_core import migrate
  from jupyter_core.application import JupyterApp
  from jupyter_core.migrate import migrate, migrate_config, migrate_dir, migrate_file, migrate_one, migrate_static_custom
  from jupyter_core.utils import ensure_dir_exists
label_desc: Use image node_id 4 for calling a global function with example usage: assert_files_equal(a, b) without return types