def process_non_authorised_user(connection, registered_users, user_name) :
    if tracLib.ACCEPT_NON_AUTHORISED_USERS:
        yt_user = to_non_authorised_youtrack_user(user_name)
        if yt_user is None:
            return None, registered_users
        else:
            if not (yt_user.login in registered_users):
                connection.importUsers([yt_user])
                registered_users.add(yt_user.login)
            return yt_user.login, registered_users
    else:
        return None, registered_users
This method tries to create new YT user for trac non-authorised user.
dataset/ETHPy150Open JetBrains/youtrack-rest-python-library/python/trac2youtrack.py/process_non_authorised_user