python3请求响应为403。（在cloudflare后面）

Question

我有cloudflare cookies，但当我看到登录页面时，发现它是403HTTP错误

但当我使用任何http代理（burp suite/fiddler等）时，它都能工作（我看到了csrfToken）

import requests
from bs4 import BeautifulSoup

istekMain = requests.get("https://www.example.com/", verify=False) // Return 200 and cookies.

cookies = istekMain.cookies.get_dict()
cookieLogin = cookies["ud_rule_vars"][1:-1]
cookieDict = {"cookieForLoginPage" : cookieLogin}
headerIstek = {
    "User-Agent" : "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.102 Safari/537.36 Edge/18.19041",
    "Accept-Encoding" : "gzip, deflate",
    "Accept" : "*/*",
    "Connection" : "keep-alive",
    "Sec-Fetch-Site" : "none",
    "Accept-Language" : "tr-TR,tr;q=0.9,en-US;q=0.8,en;q=0.7",
    "Host" : "www.example.com"
    }
istekLazim = {"ref":"","display_type":"popup","loc":""}
istekLogin = requests.get("https://www.example.com/login/", headers=headerIstek, params=istekLazim, cookies=cookieDict, verify=False)
print(istekLogin.status_code) // 403 is here. And i saw that cloudflare is open.
soup = BeautifulSoup(istekLogin.text, "html.parser")
csrfToken = soup.find("input", {"name":"csrfToken"})["value"]
print(csrfToken) // Error is "TypeError: 'NoneType' object is not subscriptable"