module Singleton::SingletonClassMethods

def _load(str) 

def _load(str)
  instance
end

def clone

that duping doesn't copy class methods?
properly clone the Singleton pattern - did you know 
def clone
  Singleton.__init__(super)
end

def inherited(sub_klass)

ensure that the Singleton pattern is properly inherited 
def inherited(sub_klass)
  super
  Singleton.__init__(sub_klass)
end