How can I restrict a Telegram bot's use to some users only?

I'm programming a Telegram bot in python with the python-telegram-bot library for python3.x It's a bot for private use only (me and some relatives), so I would like to prevent other users from using it. My idea is to create a list of authorized user IDs and the bot must not answer to messages received from users not in the list. How can I do that?

Edit: I'm quite a newbie to both python and python-telegram-bot. I'd appreciate a code snippet as example if possible =).

I found a solution from the official wiki of the library which uses a decorator. Code:

from functools import wraps

LIST_OF_ADMINS = [12345678, 87654321] # List of user_id of authorized users

def restricted(func):
    @wraps(func)
    def wrapped(update, context, *args, **kwargs):
        user_id = update.effective_user.id
        if user_id not in LIST_OF_ADMINS:
            print("Unauthorized access denied for {}.".format(user_id))
            return
        return func(update, context, *args, **kwargs)
    return wrapped

@restricted
def my_handler(update, context):
    pass  # only accessible if `user_id` is in `LIST_OF_ADMINS`.

I just @restricted each function.