code: def sample_md_notebook():
      """This is a sample md notebook with an outdated version of Jupytext
      and no kernel information, to test #908"""
      return """---
  jupyter:
    jupytext:
      text_representation:
        extension: .md
        format_name: markdown
        format_version: '1.1'
        jupytext_version: 1.1.0
  ---
  
  ```python
  1 + 1
  ```
  """
  
file_path: jupytext/tests/integration/cli/test_execute.py
imports: import shutil
  from io import StringIO
  from unittest import mock
  import pytest
  from jupytext import read, reads
  from jupytext.cli import jupytext
  from jupytext.version import __version__
label_desc: Use image node_id 9 for calling a global function with example usage: sample_md_notebook() and returns: str