code: def test_write_as_myst(tmpdir):
      """Inspired by https://github.com/mwouts/jupytext/issues/462"""
      nb = new_notebook()
      tmp_md = str(tmpdir.join("notebook.md"))
  
      jupytext.write(nb, tmp_md, fmt="myst")
  
      with open(tmp_md) as fp:
          md = fp.read()
  
      assert "myst" in md
  
imports: import pytest
  from nbformat.v4.nbbase import new_notebook
  import jupytext
  from jupytext.compare import compare
  from jupytext.formats import JupytextFormatError, divine_format, get_format_implementation, guess_format, long_form_multiple_formats, read_format_from_metadata, rearrange_jupytext_metadata, short_form_multiple_formats, update_jupytext_formats_metadata, validate_one_format
label_desc: Use image node_id 26 for calling a global function with example usage: test_write_as_myst(tmpdir) without return types