How to change this from Rails 2 to 3 - "named_scope :ordered, lambda {|*args| {:order => (args.first || 'created_at DESC')} }"?

23:20 24 Jan 2011

I have a line in my model in Rails 2

named_scope :ordered, lambda {|*args| {:order => (args.first || 'created_at DESC')} }

How to change this to Rails 3?

ruby-on-rails-3