How to use the diazo.runtrace.generate_debug_html function in diazo

except etree.LxmlError as e:
            if not(debug_mode):
                raise
            error_log = e.error_log
            runtrace = True

        if runtrace:
            from diazo.runtrace import generate_debug_html
            # Add debug information to end of body
            body = result.tree.xpath('/html/body')[0]
            debug_url = findContext(
                self.request
            ).portal_url() + '/++resource++diazo-debug'
            body.insert(
                -1,
                generate_debug_html(
                    debug_url,
                    rules=settings.rules,
                    rules_parser=getParser('rules', settings.readNetwork),
                    error_log=error_log,
                )
            )
        return result