Custom title attribute for stylesheet.

How can i add title attribute for my own custom stylesheet in wordpress within functions.php file? I find something like that

<?php
   global $wp_styles;
   $wp_styles->add('example-alt', '/themes/example/example-alt.css');
   $wp_styles->add_data('example-alt', 'title', 'Example Alternate Stylesheet');
   $wp_styles->add_data('example-alt', 'alt', TRUE);
   $wp_styles->enqueue(array('example-alt'));
?>

but I don’t know how can i use it within functions.php file or anywhere else?