leaking hose

[expat dave]

Please can someone tell me what this hose is for and where to get a replacement, it's connected to a metal box on the right hand side of the oil filter going to the engine, it's about 10in long 1in diameter and L shaped, it's leaking. not even sure what it's leaking out, the fluid is oily and clear, it could be oil I cant remember if I put new oil in before it was on sorn 2 years ago. Thanks Dave.