Render array - content with a wrapper

Here is an example of a basic rendering with content and a link

$render_array = array(
  '#type' => 'container',
  '#attributes' => array('class' => array('class1, class2')),
  'content' => array(
    '#type' => 'markup',
    '#markup' => t('This is my content!!'),
    '#weight' => 0,
  ),
  'link' => array(
    '#type' => 'link',
    '#title' => t('The link title'),
    '#href' => 'node/421',
    '#weight' => 1,
  ),
);

$output = drupal_render($render_array);