Wiki integration. Requests don't always have sessions. In particular this occurs when a request is made without a trailing slash. The Common middleware redirects when this happens, and the middleware process_request() processing stops before a session can get added. So just set an attribute on the request object for each operation. This seemed weird to me at first, but there are plenty of examples of this in the Django code base already.

"""
This file contains various helper utility functions for the messages
application.

"""


def reply_subject(subject):
    """
    Builds a subject line for a reply.
    If the subject already starts with Re: then return the subject.
    Otherwise, prepend Re: to the subject and return it.
    """
    if subject.startswith('Re: '):
        return subject
    return 'Re: ' + subject