Pushing the ConsoleHandler to the Monolog "app" logger instance in Symfony2

gistfile1.php

<?php
// ... see http://symfony.com/doc/current/components/console/introduction.html#creating-a-basic-command
namespace Acme\DemoBundle\Command;

use Symfony\Component\Console\Command\Command;
use Symfony\Component\Console\Input\InputArgument;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Input\InputOption;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Bridge\Monolog\Handler\ConsoleHandler;

class GreetCommand extends Command
{
    protected function configure() { ... }

    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $container->get('logger')->pushHandler(new ConsoleHandler($output));
        // ...
    }
}