How to Hide Custom Login Page Customizer Admin Menus

function plt_hide_login_customizer_menus() {
	//Hide "Appearance → Login Customizer".
	remove_submenu_page('themes.php', 'http://127.0.0.1/wp-admin/customize.php?autofocus[panel]=logincust_panel&url=http%3A%2F%2F127.0.0.1%2Flogin-customizer%2F');

	//Hide "Login Customizer".
	remove_menu_page('login-customizer');
	//Hide "Login Customizer → Settings".
	remove_submenu_page('login-customizer', 'login-customizer');
	//Hide "Login Customizer → Customizer".
	remove_submenu_page('login-customizer', 'http://127.0.0.1/wp-admin/customize.php?autofocus[panel]=logincust_panel&url=http%3A%2F%2F127.0.0.1%2Flogin-customizer%2F');
	//Hide "Login Customizer → Help".
	remove_submenu_page('login-customizer', 'login-customizer-help');
	//Hide "Login Customizer → Contact Us".
	remove_submenu_page('login-customizer', 'login-customizer-contact');
}

add_action('admin_menu', 'plt_hide_login_customizer_menus', 1000000000);
Where do I put this code?