How to Hide Radio Player Admin Menus

function plt_hide_radio_player_menus() {
	//Hide "Radio Player".
	remove_menu_page('radio-player');
	//Hide "Radio Player → All Players".
	remove_submenu_page('radio-player', 'radio-player');
	//Hide "Radio Player → Getting Started".
	remove_submenu_page('radio-player', 'radio-player-getting-started');
	//Hide "Radio Player → Settings".
	remove_submenu_page('radio-player', 'radio-player-settings');
	//Hide "Radio Player → Recommended Plugins".
	remove_submenu_page('radio-player', 'radio-player-recommended-plugins');
	//Hide "Radio Player → Add-Ons".
	remove_submenu_page('radio-player', 'radio-player-addons');
	//Hide "Radio Player → Upgrade".
	remove_submenu_page('radio-player', 'radio-player-pricing');
}

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

Where do I put this code?