Coolent line leak

I am looking for a cooling system part for a 2011 Cadillac CTS V Coupe. I cannot find the part on any engine diagram on the web. It is located near the oil fill cap. I have attached a picture of the part, circled with an arrow pointing to the failed plastic elbow. The elbow includes some sort of in-line valve (?) that connects to a steel line. The steel line goes into the engine or head base and is held in place with a bolted bracket. I do not know the function of the valve, or even if it is a valve. Hopefully this will help identify the part. Your help will be greatly appreciated