@classmethod<EOL><INDENT>def html_to_text(cls, html):<DEDENT>
s = cls()<EOL>s.feed(html)<EOL>unescaped_data = s.unescape(s.get_data())<EOL>return escape_for_xml(unescaped_data, tags_to_keep=s.mathml_elements)<EOL>
Return stripped HTML, keeping only MathML.