Add effect with attack to player

<?php

namespace Stick;

use pocketmine\command\Command;
use pocketmine\command\CommandSender;
use pocketmine\entity\Effect;
use pocketmine\event\entity\EntityDamageByEntityEvent;
use pocketmine\event\entity\EntityDamageEvent;
use pocketmine\event\Listener;
use pocketmine\item\Armor;
use pocketmine\item\Axe;
use pocketmine\item\Item;
use pocketmine\item\Pickaxe;
use pocketmine\item\Shovel;
use pocketmine\item\Sword;
use pocketmine\math\Vector3;
use pocketmine\Player;
use pocketmine\plugin\PluginBase;
use pocketmine\utils\Config;
use pocketmine\utils\TextFormat as TF;

class Stick extends PluginBase implements Listener
{
private $config;

public function onEnable()
{
$this->getServer()->getPluginManager()->registerEvents($this, $this);
}

public function onEntityDamage(EntityDamageEvent $event)
{

if ($event instanceof EntityDamageByEntityEvent) {

$player = $event->getEntity();
$effect = $event->getEffect();

if($effect instanceof Player){

$item = $effect->getInventory()->getItemInHand();

if($item->getId(376)){
$player->addEffect(Effect::getEffect(Effect:OISON));

}
}
}
}
}