Using User-Agent for HttplugClient

[IgorA100]

I use:

$client = new \FeedIo\Adapter\Http\Client(new Symfony\Component\HttpClient\HttplugClient());
$feedIo = new \FeedIo\FeedIo($client);
$result = $feedIo->read("Blah blah...");

But I can't figure out how to use "User-Agent".
I see the solution as an option to change:
"FeedIo\Adapter\Http\Client.php"
In "request" add the line:
$headers['User-Agent'] = 'Blah blah...';
There are other options?