def METHOD_NAME(self, sender: str, num) -> typing.List[str]:
    rng = random.Random()
    receivers = rng.sample(self.registered_users, num)
    # Sender must be != receiver but maybe there is no other registered user
    # yet, so we just send to the ft_distributor account which is registered
    # from the start
    return list(
        map(lambda a: a.replace(sender, self.ft_distributor.key.account_id),
            receivers))