simple python sha512 password thing

password.py

import getpass
import hashlib
import anymarkup


def init(filename):
    try:
        users = anymarkup.parse_file(filename)
    except:
        users = []
    finally:
        # if the file exists but is empty, our users list won't be None, but also won't be what we want
        # so just set it to an empty list also
        if type(users) != type([]):
            users = []
    return users


def prompt_user(users):
    username = getpass.getuser()
    if not username:
        username = input("Username: ")
    else:
        print(f"Username: {username}")
    # TODO: check for new user before here
    password = hashlib.sha512(getpass.getpass().encode())

    # search users
    try:
        singleUser = next(item for item in users if item["username"] == username)
        if singleUser["password"] == password.hexdigest():
            # good password, do some stuff
            return True
        else:
            # bad password, go away
            return False
    except StopIteration:
        print(f"New user {username}")
        # I really wish Python had do while
        while True:
            verifypass = hashlib.sha512(getpass.getpass("Verify Password: ").encode())
            if verifypass.hexdigest() == password.hexdigest():
                break
            else:
                print("you dun goofed, try again")
                continue
        users.append(dict(username=username, password=password.hexdigest()))
        return True


def write_file(users, filename):
    anymarkup.serialize_file(users, filename)


if __name__ == "__main__":
    #! could store this better, but the password is hashed so whatever
    # can be ini, json, json5, toml, xml or yaml
    filename = "users.json"

    # initialise list of users, will be empty list if filename doesn't exist
    users = init(filename)

    # returns true if new user, or existing user with good pass
    # returns false if bad password
    good = prompt_user(users)

    if good:
        print("Good job bud")
    else:
        print("That's a real ouchie bud")

    # don't write nothing to the file
    if len(users) != 0:
        write_file(users, filename)