How to Hide Disqus Latest Comments Addon Admin Menus

function plt_hide_disqus_latest_comments_menus() {
	//Hide the "Settings → Disqus Latest Comments" menu.
	remove_submenu_page('options-general.php', 'itsg_disqus_lastest_comments');

	//Hide the "Comments → All Comments" menu.
	remove_submenu_page('edit-comments.php', 'edit-comments.php');
	//Hide the "Comments → Disqus Latest Comments" menu.
	remove_submenu_page('edit-comments.php', 'disqus-latest-comments');
}

add_action('admin_menu', 'plt_hide_disqus_latest_comments_menus', 11);

Where do I put this code?