docs: def markdown_cell(markdown):
      r"""
      Args:
          markdown (str):
  
      Returns:
          str: json formatted ipython notebook markdown cell
  
      CommandLine:
          python -m ibeis.templates.generate_notebook --exec-markdown_cell
  
      Example:
          >>> # DISABLE_DOCTEST
          >>> from ibeis.templates.generate_notebook import *  # NOQA
          >>> markdown = '# Title'
          >>> result = markdown_cell(markdown)
          >>> print(result)
      """
      import utool as ut
      markdown_header = ut.codeblock(
          '''
            {
             "cell_type": "markdown",
             "metadata": {},
             "source": [
          '''
      )
      markdown_footer = ut.codeblock(
          '''
             ]
            }
          '''
      )
      return (markdown_header + '\n' +
              ut.indent(repr_single_for_md(markdown), ' ' * 2) +
              '\n' + markdown_footer)