I don't know what it is, but it put me off my jamming!

Fascinating, looks like an adder or perhaps a grass snake which has spent its life underground or perhaps an albino. It’s had a good meal recently though!

Grass snake I reckon as its eye has a circular pupil. Adder's pupil is a vertical slit. Colouring is unusual though for either.

Probably, the more likely explanation is that it's an escaped pet unfortunately! wild albino snakes are so incredibly rare, I really doubt you'd get one that sort of size.