import requests
from requests.auth import HTTPProxyAuth
proxyDict = {'http': '77.75.105.165', 'https': '77.75.105.165'}
auth = HTTPProxyAuth('username', 'mypassword')
r = requests.get('http://www.google.com', proxies=proxyDict, auth=auth)
Ошибка прокси-сервера Python с библиотекой запросов