code: def test_non_pep8(
      text="""def f():
      return 1
  def g():
      return 2
  
  def h():
      return 3
  """,
      ref=new_notebook(
          cells=[
              new_code_cell(
                  "def f():\n    return 1\ndef g():\n    return 2",
                  metadata={"lines_to_next_cell": 1},
              ),
              new_code_cell("def h():\n    return 3"),
          ]
      ),
  ):
      nb = jupytext.reads(text, "py")
      compare_notebooks(nb, ref)
      py = jupytext.writes(nb, "py")
      compare(py, text)
  
imports: import pytest
  from nbformat.v4.nbbase import new_code_cell, new_markdown_cell, new_notebook, new_raw_cell
  import jupytext
  from jupytext.compare import compare, compare_notebooks
label_desc: Use image node_id 4 for calling a global function with example usage: test_non_pep8(text, ref) without return types