<?php
$access = 'xxx';
$spotifyURL = 'https://api.spotify.com/v1/playlists/37i9dQZF1DWVqfgj8NZEp1/tracks';
$ch = curl_init();
$headers = [
    'Accept: application/json',
    'Content-Type: application/json',
    'Authorization: Bearer '.$access
];
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_URL, $spotifyURL);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
$json = curl_exec($ch);
$json = json_decode($json);
curl_close($ch);
echo '<pre>'.print_r($json, true).'</pre>';
?>

Parse error: syntax error, unexpected '[' on line 5