'Extend the user\'s current session.'

def keep_signed_in(self, cookies):

    new_expires = (utcnow() + SESSION_TIMEOUT)
    if ((new_expires - self.participant.session_expires) > SESSION_REFRESH):
        self.participant.set_session_expires(new_expires)
        token = self.participant.session_token
        set_cookie(cookies, SESSION, token, expires=new_expires)
