How do I have Ruby YAML dump a Hash subclass as a simple Hash?

class AutoHash < Hash
  def initialize *args
    super
    @update, @update_index = args[0][:update], args[0][:update_key] unless 
args.empty?
  end

    def [] key,*args
      if args.count > 0
        self[key][*args]
      else
        if self.has_key? key
          super key
        else
          AutoHash.new :update => self, :update_key => key
        end
      end
    end

    def []= *args
      v = args.pop
      k = args.shift
      if args.count > 0
        self[k][*args]= v
      else
        @update[@update_index] = self if @update and @update_index
        super k,v
      end
    end
end

a = AutoHash.new
a[:a][:b][:c] = 123
a[:a,:b,:c] = 321
p a # => {:a=>{:b=>{:c=>321}}}

h[:a][:b][:c] = 123
p h.path(:a,:b,:c) # => 123

h.path(:a,:b,:c)= 321
p h #=> {:a=>{:b=>{:c=>321}}}

mypath = [:a,:b,:c]
p h.path(mypath) #=> 321

test_hash = {'Classes' => variable_values.split(',')}

>> class SubHash < Hash; end
=> nil

>> a = Hash[{:a => :b}]
=> {:a=>:b}

>> a.class
=> Hash

>> b = SubHash[{:a => :b}]
=> {:a=>:b}

>> b.class
=> SubHash

def hash
    1
end