const trim = "x-amz-fwd-header-"
	for k, v := range h {
		if stringsHasPrefixFold(k, trim) {
			w.Header()[k[len(trim):]] = v
		}
	}
}

func fwdStatusToAPIError(statusCode int, resp *http.Response) *APIError {
	if statusCode < http.StatusBadRequest {
		return nil
	}
	desc := resp.Header.Get(xhttp.AmzFwdErrorMessage)
	if strings.TrimSpace(desc) == "" {