apiErr = toAPIError(ctx, vErr)
			argumentName = strings.ToLower("versionId")
			argumentValue = vErr.VersionID
		default:
			apiErr = toAPIError(ctx, vErr)
		}
		valid = false
		return
	}

	opts.MaxParts, err = parseIntHeader(bucket, object, r.Header, xhttp.AmzMaxParts)
	if err != nil {
		apiErr = toAPIError(ctx, err)
		argumentName = strings.ToLower(xhttp.AmzMaxParts)
		valid = false
		return
	}

			}
			if objRetention.Mode.Valid() {
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockMode)] = string(objRetention.Mode)
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockRetainUntilDate)] = amztime.ISO8601Format(objRetention.RetainUntilDate.UTC())
			} else {
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockMode)] = ""
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockRetainUntilDate)] = ""
			}

			c := s[i]
			if 'a' <= c && c <= 'z' {
				c -= 'a' - 'A'
			}
			b[i] = c
		}
		return b
	}
	return Map(unicode.ToUpper, s)
}

// ToLower returns a copy of the byte slice s with all Unicode letters mapped to
// their lower case.
func ToLower(s []byte) []byte {
	isASCII, hasUpper := true, false
	for i := 0; i < len(s); i++ {
		c := s[i]
		if c >= utf8.RuneSelf {
			isASCII = false
			break
		}

	if s3Err == ErrNone && retentionMode.Valid() {
		metadata[strings.ToLower(xhttp.AmzObjectLockMode)] = string(retentionMode)
		metadata[strings.ToLower(xhttp.AmzObjectLockRetainUntilDate)] = amztime.ISO8601Format(retentionDate.UTC())
	}
	if s3Err == ErrNone && legalHold.Status.Valid() {
		metadata[strings.ToLower(xhttp.AmzObjectLockLegalHold)] = string(legalHold.Status)
	}
	if s3Err != ErrNone {