您应该发布所有必需的数据，可以使用 bs4 解析登录页面以获得所需的值：
from requests import sessionfrom bs4 import BeautifulSoupdata = { 'username': 'MY_USERNAME', 'password': 'MY_PASSWORD'}head = {"User-Agent":"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36"}with session() as s: soup = BeautifulSoup(s.get("https://fif.com/login").content) form_data = soup.select("form[action^=/login?task] input") data.update({inp["name"]: inp["value"] for inp in form_data if inp["name"] not in data}) s.post('https://fif.com/login?task=user.login', data=data, headers=head) resp = s.get('https://fif.com/tools/capacity')如果您提出要求并查看Chrome工具或Firebug，则表单数据如下所示：
username:foopassword:barreturn:aW5kZXgucGhwP29wdGlvbj1jb21fdXNlcnMmdmlldz1wcm9maWxld68a2b40daf7b6c8eaa3a2f652f7ee62:1
