code: def test_meaningfull_error_write_myst_missing(tmpdir):
      nb_file = tmpdir.join("notebook.ipynb")
      jupytext.write(new_notebook(), str(nb_file))
  
      with pytest.raises(ImportError, match=PLEASE_INSTALL_MYST):
          jupytext_cli([str(nb_file), "--to", "md:myst"])
  
imports: import json
  import unittest.mock
  from textwrap import dedent
  import pytest
  from nbformat.v4.nbbase import new_notebook
  from tornado.web import HTTPError
  import jupytext
  from jupytext.cli import jupytext
  from jupytext.compare import compare
  from jupytext.formats import JupytextFormatError, get_format_implementation, guess_format
  from jupytext.myst import CODE_DIRECTIVE, MystMetadataParsingError, matches_mystnb, myst_extensions, myst_to_notebook
label_desc: Use image node_id 8 for calling a global function with example usage: test_meaningfull_error_write_myst_missing(tmpdir) without return types