code: def test_mark_regex_escape(pytester: Pytester) -> None:
      """@pytest.mark.filterwarnings should not try to escape regex characters (#3936)"""
      pytester.makepyfile(
          r"""
          import pytest, warnings
  
          @pytest.mark.filterwarnings(r"ignore:some \(warning\)")
          def test_foo():
              warnings.warn(UserWarning("some (warning)"))
      """
      )
      result = pytester.runpytest()
      assert WARNINGS_SUMMARY_HEADER not in result.stdout.str()
  
imports: import os
  import sys
  import warnings
  from typing import List
  from typing import Optional
  from typing import Tuple
  import pytest
  from _pytest.fixtures import FixtureRequest
  from _pytest.pytester import Pytester
label_desc: Use image node_id 13 for calling a global function with example usage: test_mark_regex_escape(pytester) without return types