What part is this?
 

I have a 2017 CC that I replaced the water pump when putting the intake manifold back on I noticed this sensor (?) broken on the inside what is it and what does it do? Thank you
https://cimg8.ibsrv.net/gimg/volkswa...c023bc5bf.jpeg
https://cimg9.ibsrv.net/gimg/volkswa...601887ac6.jpeg