code: def test_re_emit_non_match_single(self) -> None:
      with pytest.warns(UserWarning, match="v2 warning"):
          with pytest.warns(UserWarning, match="v1 warning"):
              warnings.warn("v1 warning", UserWarning)
              warnings.warn("non-matching v2 warning", UserWarning)
  
imports: import warnings
  from typing import List
  from typing import Optional
  from typing import Type
  import pytest
  from _pytest.pytester import Pytester
  from _pytest.recwarn import WarningsRecorder
label_desc: Use image node_id 20 for calling the TestWarns obj's underlying member method code with example usage: obj.test_re_emit_non_match_single() without return types