Function check_slice_answer 

pub fn check_slice_answer(
    status: u16,
    body: &[u8],
    keys: &Keys,
    request: &SliceRequest,
) -> Result<Answer>

Checks an answer of the slice endpoint (5.6) against request: stale and pending are not answers there; ok is a page, checked as 5.6 says (its members, the slice id, next, then each member’s receipt through step 6 of 10.1, membership, asof, trust and key order after after); every other outcome as in 5.5.