How to send ChangeDimensionPacket

I'm wanting to send the ChangeDimensionPacket but I'm not sure how to send packets.

 

How to use ChangeDimensionPacket:

PHP:

<?php
$pk = new ChangeDimensionPacket()
$pk->dimension = 1 //1 is the nether; 0 is the overworld
$pk->x = (int) $x //define X
$pk->y = (int) $y //define Y
$pk->z = (int) $z //define Z
$player->dataPacket($pk) //$player must be an instance of a pocketmine/Player

 

Thanks.