How to Hide Menu Image Admin Menus

function plt_hide_menu_image_menus() {
	//Hide "Menu Image".
	remove_menu_page('menu-image-options');
	//Hide "Menu Image → Menu Image".
	remove_submenu_page('menu-image-options', 'menu-image-options');
	//Hide "Menu Image → Affiliation".
	remove_submenu_page('menu-image-options', 'menu-image-options-affiliation');
	//Hide "Menu Image → Contact Us".
	remove_submenu_page('menu-image-options', 'menu-image-options-contact');
	//Hide "Menu Image → Support Forum".
	remove_submenu_page('menu-image-options', 'menu-image-options-wp-support-forum');
	//Hide "Menu Image → Upgrade".
	remove_submenu_page('menu-image-options', 'menu-image-options-pricing');
}

add_action('admin_menu', 'plt_hide_menu_image_menus', 1000000000);

Where do I put this code?