Downloading image from url using python-requests recieving error 403:Forbidden

So Im trying to download image but server response is "403". I have tried using other user-agents if it has any sense but it doesn't work. With other links code works well. I don't know how i can circumvent server or smth.

import requests
import shutil

headers = {
    'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36'
}


r = requests.get('https://s8.mkklcdnv6temp.com/mangakakalot/b1/bd926355/chapter_3/1.jpg', 
    headers=headers,
    stream=True)
if r.status_code == 200:
    with open("img.png", 'wb') as f:
        r.raw.decode_content = True
        shutil.copyfileobj(r.raw, f)
else:
    print('failure')