u, err := uuid.NewRandom()
	if err != nil {
		logger.CriticalIf(GlobalContext, err)
	}
	return u[:]
}

// Create an s3 compatible MD5sum for complete multipart transaction.
func getCompleteMultipartMD5(parts []CompletePart) string {
	var finalMD5Bytes []byte
	for _, part := range parts {
		md5Bytes, err := hex.DecodeString(canonicalizeETag(part.ETag))
		if err != nil {

	if fi.Metadata["etag"] == "" {
		if opts.UserDefined["etag"] != "" {
			fi.Metadata["etag"] = opts.UserDefined["etag"]
		} else { // fallback if not already calculated in handler.
			fi.Metadata["etag"] = getCompleteMultipartMD5(parts)
		}
	}

	// Save the consolidated actual size.
	if opts.ReplicationRequest {
		fi.Metadata[ReservedMetadataPrefix+"actual-size"] = opts.UserDefined["X-Minio-Internal-Actual-Object-Size"]

				{ETag: validPartMD5, PartNumber: 2},
			},
		},
	}

	// on successful complete multipart operation the s3MD5 for the parts uploaded will be returned.
	s3MD5 := getCompleteMultipartMD5(inputParts[3].parts)

	// generating the response body content for the success case.