Passing cookies while logging in

I would like to integrate python Selenium and Requests modules to authenticate on a website.

I am using the following code:

import requests
from selenium import webdriver

driver = webdriver.Firefox()
url = "some_url" #a redirect to a login page occurs
driver.get(url) #the login page is displayed

#making a persistent connection to authenticate
params = {'os_username':'username', 'os_password':'password'}
s = requests.Session()
resp = s.post(url, params) #I get a 200 status_code

#passing the cookies to the driver
driver.add_cookie(s.cookies.get_dict())

The problem is that when I enter the browser the login authentication is still there when I try to access the url even though I passed the cookies generated from the requests session.

How can I modify the code above to get through the authentication web page?

Answer

I finally found out what the problem was. Before making the post request with the requests library, I should have passed the cookies of the browser first. The code is as follows:

import requests
from selenium import webdriver

driver = webdriver.Firefox()
url = "some_url" #a redirect to a login page occurs
driver.get(url)

#storing the cookies generated by the browser
request_cookies_browser = driver.get_cookies()

#making a persistent connection using the requests library
params = {'os_username':'username', 'os_password':'password'}
s = requests.Session()

#passing the cookies generated from the browser to the session
c = [s.cookies.set(c['name'], c['value']) for c in request_cookies_browser]

resp = s.post(url, params) #I get a 200 status_code

#passing the cookie of the response to the browser
dict_resp_cookies = resp.cookies.get_dict()
response_cookies_browser = [{'name':name, 'value':value} for name, value in dict_resp_cookies.items()]
c = [driver.add_cookie(c) for c in response_cookies_browser]

#the browser now contains the cookies generated from the authentication    
driver.get(url)