content: import dash
  from dash.dash_table import DataTable
  
  
  def get_app(markdown_options):
  
      app = dash.Dash(__name__)
  
      props = dict(
          id="table",
          columns=[dict(name="a", id="a", type="text", presentation="markdown")],
          data=[dict(a="<h1>html h1 heading</h1>")],
      )
  
      if markdown_options is not None:
          props["markdown_options"] = markdown_options
  
      app.layout = DataTable(**props)
  
      return app
  
  
  def test_tmdh001_html_not_allowed(test):
      test.start_server(get_app(None))
  
      h1_elements = test.find_elements("h1")
  
      assert len(h1_elements) == 0
      assert test.get_log_errors() == []
  
  
  def test_tmdh002_html_allowed(test):
      test.start_server(get_app(dict(html=True)))
  
      h1_elements = test.find_elements("h1")
  
      assert len(h1_elements) == 1
      assert test.get_log_errors() == []
  