code: def test_deprecated_formats_cause_warning(
      tmpdir, content_toml="default_jupytext_formats = 'ipynb,md'"
  ):
      jupytext_toml = tmpdir.join("jupytext.toml")
      jupytext_toml.write(content_toml)
  
      config = load_jupytext_configuration_file(str(jupytext_toml))
      with pytest.warns(FutureWarning, match="use 'formats'"):
          assert (
              config.default_formats(str(tmpdir.join("test.md")))
              == "ipynb,md"
          )
  
file_path: jupytext/tests/functional/config/test_config.py
imports: import os
  import pytest
  from jupytext.config import find_jupytext_configuration_file, load_jupytext_configuration_file
label_desc: Use image node_id 5 for calling a global function with example usage: test_deprecated_formats_cause_warning(tmpdir, content_toml) without return types