HTTP错误500：Twitter API OAuth

Question

我正在尝试使用OAuth连接到Twitter API，但我继续获取"localhost is currently unable to handle this request" HTTP ERROR 500。这是我的代码：

<?php
require "twitteroauth/autoload.php";

use Abraham\TwitterOAuth\TwitterOAuth;

$consumer_key = "";       //left blank here intentionally.
$consumer_secret = "";
$access_token = "";
$access_token_secret = "";

$connection = new TwitterOAuth($consumer_key, $consumer_secret, $access_token, $access_token_secret);
$content = $connection->get("account/verify_credentials");
print_r($content);
?>

可能是什么问题？