Get subuser list PHP

subuser.php

<?php

$url = 'https://api.sendgrid.com/';
$user = 'SG_username';
$pass = 'SG_password';

$params = array(
    'api_user'  => $user,
    'api_key'   => $pass,
    'task'      => 'get',
  );
  
$request =  $url.'apiv2/customer.profile.json';

// Generate curl request
$session = curl_init($request);
// Tell curl to use HTTP POST
curl_setopt ($session, CURLOPT_POST, true);
// Tell curl that this is the body of the POST
curl_setopt ($session, CURLOPT_POSTFIELDS, $params);
// Tell curl not to return headers, but do return the response
curl_setopt($session, CURLOPT_HEADER, false);
// Tell PHP not to use SSLv3 (instead opting for TLS)
curl_setopt($session, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1_2);
curl_setopt($session, CURLOPT_RETURNTRANSFER, true);

// obtain response
$response = curl_exec($session);
curl_close($session);

	
// print everything out
$decodedResp = json_decode($response);
$fp = fopen('subusers.txt', 'w');
$subuserArray = array();
foreach ($decodedResp as $singleSubuser)
{
	array_push($subuserArray, $singleSubuser->username);

}
foreach( $subuserArray as $subuser){
	fputcsv($fp, explode(',', $subuser));
}

fclose($fp);
?>