code: def test_horizontal_rule(self):
      self.assertMarkdownRenders("--- -- ---", "<hr />")
  
file_path: markdown/tests/test_syntax/extensions/test_smarty.py
imports: from markdown.test_tools import TestCase
label_desc: Use image node_id 8 for calling the TestSmarty obj's underlying member method code with example usage: obj.test_horizontal_rule() without return types