Getting URL of a Group’s image field from Settings page in Meta Box

In the previous tutorial I showed how we can get the URL of an image field from a Settings page when using Meta Box. This members-only tutorial shows how the same can be done when the image field is inside a group.

Option name of the Settings page: my_options

Field ID Prefix set for the field group attached to the Settings page: sitewide_

ID of the Group field: branding

ID of the Single Image-type field inside the branding group: logo

Here's the custom function: