import requests
s = requests.session()
# 第一步：发送一个请求，用于设置请求中的cookies
cookies = dict(cookies_are='cookie1')
# tips: http://httpbin.org能够用于测试http请求和响应
r1 = s.get(url='http://httpbin.org/cookies', cookies=cookies)
print(r1.text)
# 第二步：发送一个请求，用于再次设置请求中的cookies
cookies = dict(cookies_are='cookie2')
r2 = s.get(url='http://httpbin.org/cookies', cookies=cookies)
print(r2.text)

# r1.text
{
 "cookies": {
  "cookies_are": "cookie1"
 }
}
# t2.text
{
 "cookies": {
  "cookies_are": "cookie2"
 }
}

import requests
s = requests.session()
s.cookies.update({'cookies_are': 'cookie'})
r = s.get(url='http://httpbin.org/cookies')
print(r.text)

import requests
jar = requests.cookies.RequestsCookieJar()
jar.set('tasty_cookie', 'yum', domain='httpbin.org', path='/cookies')
jar.set('gross_cookie', 'blech', domain='httpbin.org', path='/elsewhere')
url = 'http://httpbin.org/cookies'
r = requests.get(url, cookies=jar)
print(r.text)

{
 "cookies": {
  "tasty_cookie": "yum"
 }
}