>>> url = 'http://example.com/some/cookie/setting/url'
>>> r = requests.get(url)
>>> r.cookies['example_cookie_name']
'example_cookie_value'

>>> url = 'http://httpbin.org/cookies'
>>> cookies = dict(cookies_are='working')
>>> r = requests.get(url, cookies=cookies)
>>> r.text
'{"cookies": {"cookies_are": "working"}}'

[
{
    "domain": ".fdworlds.net",
    "expirationDate": 1474141809,
    "hostOnly": false,
    "httpOnly": false,
    "name": "__utma",
    "path": "/",
    "secure": false,
    "session": false,
    "storeId": "0",
    "value": "161727595.461491843.1410962347.1410962347.1411069809.3",
    "id": 1
},
{
    "domain": ".fdworlds.net",
    "expirationDate": 1411071609,
    "hostOnly": false,
    "httpOnly": false,
    "name": "__utmb",
    "path": "/",
    "secure": false,
    "session": false,
    "storeId": "0",
    "value": "161727595.1.10.1411069809",
    "id": 2
},
{
    "domain": ".fdworlds.net",
    "hostOnly": false,
    "httpOnly": false,
    "name": "__utmc",
    "path": "/",
    "secure": false,
    "session": true,
    "storeId": "0",
    "value": "161727595",
    "id": 3
},
{
    "domain": ".fdworlds.net",
    "expirationDate": 1426837809,
    "hostOnly": false,
    "httpOnly": false,
    "name": "__utmz",
    "path": "/",
    "secure": false,
    "session": false,
    "storeId": "0",
    "value": "161727595.1410962347.1.1.utmcsr=(direct)|utmccn=(direct)|utmcmd=(none)",
    "id": 4
},
{
    "domain": ".fdworlds.net",
    "expirationDate": 1411071610,
    "hostOnly": false,
    "httpOnly": false,
    "name": "_ym_visorc_23263192",
    "path": "/",
    "secure": false,
    "session": false,
    "storeId": "0",
    "value": "b",
    "id": 5
},
{
    "domain": ".www.fdworlds.net",
    "hostOnly": false,
    "httpOnly": false,
    "name": "PHPSESSID",
    "path": "/",
    "secure": false,
    "session": true,
    "storeId": "0",
    "value": "fbbj4cj8pqn10asdkncbp5",
    "id": 6
},
{
    "domain": "www.fdworlds.net",
    "hostOnly": true,
    "httpOnly": false,
    "name": "b",
    "path": "/",
    "secure": false,
    "session": true,
    "storeId": "0",
    "value": "b",
    "id": 7
}
]

import requests
from bs4 import *
url = 'http://www.fdworlds.net'
data = {
    'login':'login',
    'pass':'pass'
}
headers = {
    'User-Agent' : 'Mozilla/5.0 (Windows NT 6.1; WOW64; rv:32.0) Gecko/20100101 Firefox/32.0',
    'Accept' : 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
    'Accept-Language' : 'ru-RU,ru;q=0.8,en-US;q=0.5,en;q=0.3',
    'Accept-Encoding' : 'gzip, deflate',
}
s = requests.Session()
resp = s.post('https://www.fdworlds.net/auth.php', headers=headers, data=data)
resp.encoding = 'windows-1251'
soup = BeautifulSoup(resp.text)
action = soup.find('form').get('action')
resp = s.post(action,headers=headers,data=data)

        private const string _site = "https://www.fdworlds.net/";
        private const string _login = "";
        private const string _passw = "";
        private CookieContainer _cookie = new CookieContainer();

        private string POST(string _site, string _data, string _referer)
        {
            HttpWebRequest postRequest = (HttpWebRequest) WebRequest.Create(_site);
            {
                postRequest.Method = "POST";
                postRequest.Timeout = 100000;
                postRequest.Host = "www.fdworlds.net";
                postRequest.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:28.0) Gecko/20100101 Firefox/28.0";
                postRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
                postRequest.Referer = _referer;
                postRequest.CookieContainer = _cookie;
                postRequest.ContentType = "application/x-www-form-urlencoded";
                byte[] sentData = Encoding.GetEncoding(1251).GetBytes(_data);
                postRequest.ContentLength = sentData.Length;
                Stream sendStream = postRequest.GetRequestStream();
                sendStream.Write(sentData, 0, sentData.Length);
                sendStream.Close();
            }
            WebResponse resp = postRequest.GetResponse();
            Stream ReceiveStream = resp.GetResponseStream();
            StreamReader sr = new StreamReader(ReceiveStream, Encoding.GetEncoding(1251));
            Char[] read = new Char[256];
            int count = sr.Read(read, 0, 256);
            string Out = String.Empty;
            while (count > 0)
            {
                String str = new String(read, 0, count);
                Out += str;
                count = sr.Read(read, 0, 256);
            }
            return Out;
        }

        private string GET(string _site, string _data, string _referer)
        {
            HttpWebRequest getRequest = (HttpWebRequest) WebRequest.Create(_site + "?" + _data);
            {
                getRequest.Method = "GET";
                getRequest.Host = "www.fdworlds.net";
                getRequest.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:28.0) Gecko/20100101 Firefox/28.0";
                getRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8";
               if (_referer != null)
                   getRequest.Referer = _referer;
                getRequest.CookieContainer = _cookie;
            }
            WebResponse resp = getRequest.GetResponse();
            Stream ReceiveStream = resp.GetResponseStream();
            StreamReader sr = new StreamReader(ReceiveStream, Encoding.GetEncoding(1251));
            Char[] read = new Char[256];
            int count = sr.Read(read, 0, 256);
            string Out = String.Empty;
            while (count > 0)
            {
                String str = new String(read, 0, count);
                Out += str;
                count = sr.Read(read, 0, 256);
            }
            return Out;
        }

        public Form1()
        {
            InitializeComponent();
        }

        private void btnConnect_Click(object sender, EventArgs e)
        {
            txb_text.Text = POST(_site + "enter.php", "login=" + _login + "&pass=" + _passw, "https://www.fdworlds.net/auth.php");
            txb_text.Text = GET(_site + "inv_user.php", " ", "http://www.fdworlds.net/inv_user.php");
        }
    }
}