How to render a Commerce pane programmatically? I've the following code:

$panes = commerce_checkout_panes();
$payment_pane = $panes['commerce_payment'];


which loads one of Commerce pane which contains the array like:

array (size=15)
  'title' =&gt; string 'Payment' (length=7)
  'page' =&gt; string 'review' (length=6)
  'file' =&gt; string 'includes/commerce_payment.checkout_pane.inc' (length=43)
  'base' =&gt; string 'commerce_payment_pane' (length=21)
...


How do I render that pane programmatically?

This is part of commerce_checkout_form_review form (which is normally present at /checkout/%/review), but I need to render only payment part (checkboxes) but in different place.
Panes are forms. Run them through drupal_get_form but you'll need to pass in some extra options:

require_once drupal_get_path('module', $payment_pane['module']) . '/' . $payment_pane['file'];
$order = commerce_order_load($order_id);
$payment_form = drupal_get_form($payment_pane['callbacks']['checkout_form'], $payment_pane, $order);
$output = drupal_render($payment_form);