fn byte_encode<D: EncodingSize>(
vals: &Array<FieldElement, U256>,
) -> Array<u8, <D as EncodingSize>::EncodedPolynomialSize>fn byte_encode<D: EncodingSize>(
vals: &Array<FieldElement, U256>,
) -> Array<u8, <D as EncodingSize>::EncodedPolynomialSize>