Получить курс доллара на forex

func forex() string {
	client := &http.Client{
		Timeout: 10 * time.Second,  
	}

 	req, err := http.NewRequest("GET", "https://www.investing.com/currencies/usd-rub", nil)
	if err != nil {
		log.Fatal(err)
	}

 	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537")

	res, err := client.Do(req)
	if err != nil {
		log.Println(err)
	}
	defer res.Body.Close()
	if res.StatusCode != 200 {
		log.Printf("status code error: %d %s", res.StatusCode, res.Status)
	}

	// Load the HTML document
	doc, err := goquery.NewDocumentFromReader(res.Body)
	if err != nil {
		log.Println(err)
	}

	var price string
	doc.Find("span[data-test='instrument-price-last']").Each(func(index int, item *goquery.Selection) {
		price = item.Text()
		fmt.Println(price)
	})

	return price
}