Given a template Name I will gues using its
        extension if we should autoscape or not.
        Default autoscaped extensions: ('html', 'xhtml', 'htm', 'xml')

def guess_autoescape(self, template_name):
        """Given a template Name I will gues using its
        extension if we should autoscape or not.
        Default autoscaped extensions: ('html', 'xhtml', 'htm', 'xml')
        """
        if template_name is None or '.' not in template_name:
            return False
        ext = template_name.rsplit('.', 1)[1]
        return ext in ('html', 'xhtml', 'htm', 'xml')