Thank you, Eric for your comments! I see now what doese the 'review' link mean :)   You are right the send_error should be a method not a class variable. I changed it in a new patch. As regards the responses I prefer don't change it to a class attribute because in documentation it is mentioned as a class variable in several places. I also checked that :attr:`send_error` does generate a link to send_error method in html.