pocketmine\Player::setBanned PHP Method

    public function setBanned($value)
    {
        if ($value === true) {
            $this->server->getNameBans()->addBan($this->getName(), null, null, null);
            $this->kick(TextFormat::RED . "You have been banned");
        } else {
            $this->server->getNameBans()->remove($this->getName());
        }
    }