each user one session in django - also works on redis as cache engine

login_one_session.py

def login_one_session(request, user): 
    from importlib import import_module
    from django.core.cache import cache

    # Get Session Key and Prefix 
    from django.contrib.auth import SESSION_KEY
    from django.contrib.sessions.backends.cache import KEY_PREFIX

    # login authorized user
    login(request, user)

    # remove prefix of all session key
    all_keys = [key.split(KEY_PREFIX)[-1] for key in cache.keys(KEY_PREFIX+'*')]

    # get session engine 
    engine = import_module(settings.SESSION_ENGINE)
    SessionStore = engine.SessionStore

    # get curent user session key
    current_session_key = request.session.session_key

    # search for duplicate key
    for key in all_keys:
        # try to extract user id from each session
        session = SessionStore(key)
        user_id = session.get(SESSION_KEY)
        
        # if finde another session key from curent user, delete that!
        if user_id and int(user_id) is request.user.id and current_session_key is not session.session_key:
            cache.delete_pattern(KEY_PREFIX + session.session_key)