How to use proxies with Python Requests

import getpass
from urllib.parse import quote

import requests
from requests.exceptions import ConnectionError, ProxyError, SSLError, Timeout


def endpoints(host, username, password):
    auth = f"{quote(username, safe='')}:{quote(password, safe='')}"
    return [
        f"socks5h://{auth}@{host}:1080",  # requires requests[socks]
        f"http://{auth}@{host}:3128",    # HTTP proxy; HTTPS uses CONNECT
    ]


def proxies_for(proxy_url):
    return {"http": proxy_url, "https": proxy_url}

def fetch_with_fallback(session, url, proxy_urls, ca_bundle=True):
    # Ignore environment proxy/bypass overrides. Configure custom CA bundles
    # with ca_bundle="/path/to/ca.pem" if needed; verification stays enabled.
    if ca_bundle is not True and (not isinstance(ca_bundle, str) or not ca_bundle):
        raise ValueError("Use True or an explicit CA bundle path")
    session.trust_env = False
    for proxy_url in proxy_urls:
        try:
            response = session.get(
                url,
                proxies=proxies_for(proxy_url),
                timeout=(5, 15),
                verify=ca_bundle,
            )
            response.raise_for_status()
            return response
        except SSLError:
            raise RuntimeError("TLS verification failed; not retried") from None
        except (ProxyError, ConnectionError, Timeout):
            # Never print the authenticated URL or the transport exception.
            continue
    raise RuntimeError("All configured proxy transports failed") from None


if __name__ == "__main__":
    host = input("Proxy host from your account (without scheme or port): ").strip()
    username = input("Proxy username: ")
    password = getpass.getpass("Proxy password: ")
    SOCKS5, HTTP = endpoints(host, username, password)
    with requests.Session() as session:
        try:
            response = fetch_with_fallback(
                session,
                "https://api.ipify.org?format=json",
                [SOCKS5, HTTP],
            )
            print("Exit IP:", response.json()["ip"])
        except (requests.RequestException, RuntimeError):
            raise SystemExit("Request failed; check the endpoint, credentials and TLS settings") from None