// as mandated by RFC 3986 Section 6.2.3.
func removeEmptyPort(host string) string {
	if hasPort(host) {
		return strings.TrimSuffix(host, ":")
	}
	return host
}

// Copied from http.NewRequest but implemented to ensure we reuse `url.URL` instance.
func (c *Client) newRequest(ctx context.Context, u url.URL, body io.Reader) (*http.Request, error) {
	rc, ok := body.(io.ReadCloser)
	if !ok && body != nil {