docs: def check_file_version(notebook, source_path, outputs_path):
      """Raise if file version in source file would override outputs"""
      if not insert_or_test_version_number():
          return
  
      _, ext = os.path.splitext(source_path)
      if ext.endswith('.ipynb'):
          return
      version = notebook.metadata.get('jupytext', {}).get('text_representation', {}).get('format_version')
      format_name = format_name_for_ext(notebook.metadata, ext)
  
      fmt = get_format_implementation(ext, format_name)
      current = fmt.current_version_number
  
      # Missing version, still generated by jupytext?
      if notebook.metadata and not version:
          version = current
  
      # Same version? OK
      if version == fmt.current_version_number:
          return
  
      # Version larger than minimum readable version
      if (fmt.min_readable_version_number or current) <= version <= current:
          return
  
      raise JupytextFormatError("File {} is in format/version={}/{} (current version is {}). "
                                "It would not be safe to override the source of {} with that file. "
                                "Please remove one or the other file."
                                .format(os.path.basename(source_path),
                                        format_name, version, current,
                                        os.path.basename(outputs_path)))