invp := InvalidPart{
				PartNumber: part.PartNumber,
				GotETag:    part.ETag,
			}
			return oi, invp
		}
		expPart := currentFI.Parts[partIdx]

		// ensure that part ETag is canonicalized to strip off extraneous quotes
		part.ETag = canonicalizeETag(part.ETag)
		expETag := tryDecryptETag(objectEncryptionKey, expPart.ETag, kind == crypto.S3)
		if expETag != part.ETag {
			invp := InvalidPart{

}

// Parse parses and returns a go.mod file.
//
// file is the name of the file, used in positions and errors.
//
// data is the content of the file.
//
// fix is an optional function that canonicalizes module versions.
// If fix is nil, all module versions must be canonical ([module.CanonicalVersion]
// must return the same string).
func Parse(file string, data []byte, fix VersionFixer) (*File, error) {

	// operations on 64-bit registers, which is much faster than
	// bytewise processing.
	addr uint128

	// Details about the address, wrapped up together and canonicalized.
	z unique.Handle[addrDetail]
}

// addrDetail represents the details of an Addr, like address family and IPv6 zone.
type addrDetail struct {
	IsV6   bool   // IPv4 is false, IPv6 is true.