如何创建默认的“来宾”会话,以便“设计助手”当前用户将显示我的来宾用户?

def set_user
  if current_user.blank?
    user = User.where(:email => "guest@mycompany").first
    if user.blank?
      redirect_to new_user_registration_path
    else
      sign_in(user) # Why was this so hard to find out? I had to read all of the Devise code.
    end
  end
end