docs: def markdown(
          source: str = None,
          source_path: str = None,
          preserve_lines: bool = False,
          font_size: float = None,
          **kwargs
  ):
      """
      Renders the specified source string or source file using markdown and 
      adds the resulting HTML to the notebook display.
  
      :param source:
          A markdown formatted string.
      :param source_path:
          A file containing markdown text.
      :param preserve_lines:
          If True, all line breaks will be treated as hard breaks. Use this
          for pre-formatted markdown text where newlines should be retained
          during rendering.
      :param font_size:
          Specifies a relative font size adjustment. The default value is 1.0,
          which preserves the inherited font size values. Set it to a value
          below 1.0 for smaller font-size rendering and greater than 1.0 for
          larger font size rendering.
      :param kwargs:
          Any variable replacements to make within the string using Jinja2
          templating syntax.
      """
      r = _get_report()
  
      result = render_texts.markdown(
          source=source,
          source_path=source_path,
          preserve_lines=preserve_lines,
          font_size=font_size,
          **kwargs
      )
      r.library_includes += result['library_includes']
  
      r.append_body(result['body'])
      r.stdout_interceptor.write_source(
          '{}\n'.format(textwrap.dedent(result['rendered']))
      )