The code is overcomplicated and somewhat rough for what it does. Python docs has 4 line snippet that you just copypaste if you need:

    import secrets
    # On standard Linux systems, use a convenient dictionary file.
    # Other platforms may need to provide their own word-list.
    with open('/usr/share/dict/words') as f:
        words = [word.strip() for word in f]
        password = ' '.join(secrets.choice(words) for i in range(4))

https://docs.python.org/3/library/secrets.html#recipes-and-b...

Also EFF had prepared convenient wordlists specifically for password generation: https://www.eff.org/deeplinks/2016/07/new-wordlists-random-p...