import  requests

url="https://www.douban.com/accounts/login"     #action属性
params={
   "source":"index_nav",               #input标签下的name
   "form_email":"xxxxxx",              #input标签下的name
   "form_password":"xxxxxx"              #input标签下的name

}
html=requests.post(url,data=params)
print(html.text)