How to Hide the "ThreatPoint Email Validator" Admin Menu

function plt_hide_threatpoint_email_validator_menus() {
	//Hide the "Settings → ThreatPoint Email Validator" menu.
	remove_submenu_page('options-general.php', 'ThreatPoint-email-page');
}

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

Where do I put this code?