class_docstr: Test the markdown.extensions.codehilite.CodeHilite class. 
class_docstr_tok: ["Test","the","markdown.extensions.codehilite.CodeHilite","class","."]
code: def test_codehilite_guess_lang_plain_text(self):
      if has_pygments:
          expected = (
              '<div class="codehilite"><pre><span></span><code><span class="err">plain text</span>\n'
              "</code></pre></div>"
          )
      else:
          expected = (
              '<pre class="codehilite"><code>plain text\n'
              "</code></pre>"
          )
      # This will be difficult to guess.
      self.assertOutputEquals("plain text", expected, guess_lang=True)
  
imports: from markdown.test_tools import TestCase
  from markdown.extensions.codehilite import CodeHiliteExtension, CodeHilite
  from markdown import extensions, treeprocessors
  import os
  import xml.etree.ElementTree
label_desc: Use image node_id 5 for calling the TestCodeHiliteClass obj's underlying member method code with example usage: obj.test_codehilite_guess_lang_plain_text() without return types