Creating reusable emails

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2

So I need to register the Mailer class on the model?

$articleMailer = new ArticleMailer();
$this->getEventManager()->on($ArticleMailer);

Now when I add an article it gets triggered but it is showing errors:

Argument 1 passed to App\Mailer\ArticleMailer::onPost() must be an instance of App\Mailer\Event, instance of Cake\Event\Event given