Use the blog collection in your functions (and filters)

If you want to use the collection of blogs which created the plugin in your functions (and filters) you can write code like this:

function my_print_something() {
    foreach ( MslsBlogCollection::instance()->get() as $blog ) {
        printf(
            '<link rel="alternate" hreflang="%1$s" href="http://%1$s.example.com/" />'
            $blog->get_language()
        );
    }
}
add_action( 'wp_head', 'my_print_something' );

The above code prints the link references to your blogs in all html headers of the frontend output.