code: def to_html(self, **kwargs):
          
          super(HorizontalRule, self).__init__(**kwargs)
          return '<hr%s/>\n' % self.html_attributes()
docs: Render as html
  
          :returns: the html representation (<hr>)
          :rtype: str
  
          We pass the kwargs on to the base class so an exception is raised
          if invalid keywords were passed. See:
  
          http://stackoverflow.com/questions/13124961/
          how-to-pass-arguments-efficiently-kwargs-in-python