class AppnexusApi::OperatingSystemExtendedService < AppnexusApi::Service
  def initialize(connection)
    @read_only = true
    super(connection)
  end

  def plural_name
    'operating-systems-extended'
  end
end

class AppnexusApi::OperatingSystemExtendedService < AppnexusApi::Service
  def initialize(connection)
    @read_only = true
    super(connection)
  end
end

--- 
+++ 
@@ -3,4 +3,8 @@
     @read_only = true
     super(connection)
   end
+
+  def plural_name
+    'operating-systems-extended'
+  end
 end
Fix plural name for extended OS
