Oil pipe at back of the engine what's it called

[Golwyn]

Hello the pipe at the back of the engine on my Audi A4 1.8 petrol b5 next to the bulkhead has totally split and need to no what it's called to try and get a new one as the oil is !Removed! out and the top of the engine is now nocking well stoped driving it when it happened thanks for the help ps how hard is it to change it .