Air cleaner assembly

[Lurch]

Quick question please, noticed today behind the rear passenger light assembly the pipe work for the air box , there is a braided type hose which has a plastic bag covering it tie wrapped round the pipe is this normal ? Not noticed before and as car only done 7k from new looks like it was there from new but may be wrong, hopefully someone can answer the question please.

[Lurch]

Think I have just answered it myself as just found a picture on here which shows the same plastic bag on the pipe work. Aem air intake post.