How to convert PT time to time format in php?

This post convert PT time to time format in php.

1. Code:

    <?php 
	function convertTimePTToTimeFormat($timePt){
	    $timePt = str_replace("PT", "", $timePt);
	    $arrTime = explode("H", $timePt);
	    $h = $arrTime[0];
	    $m = str_replace("M", "", $arrTime[1]);
	    if(!isset($h) || trim($h) === ''){
			$h = "00";
		}
		if(!isset($m) || trim($m) === ''){
			$m = "00";
		}
	    return $h . ":" . $m . ":00";
	}
	$timeD = "PT17H30M";
	$str = convertTimePTToTimeFormat($timeD);
    ?> 

2. Example:

Input:

PT17H30M

Output:

17:30:00