Get WooCommerce product type by product ID

/**
 * Gets WooCommerce product type (e.g., `simple`, `external`, `grouped`, `variable`, `variation`) by product ID.
 *
 * @see https://wpcodebook.com/snippets/get-woocommerce-product-type-by-product-id/
 * @see https://github.com/woocommerce/woocommerce/blob/8.0.1/plugins/woocommerce/includes/class-wc-product-factory.php#L77
 *
 * @param  int $product_id Product ID.
 * @return string|false
 */
function wpcodebook_get_product_type( $product_id ) {
	return WC_Product_Factory::get_product_type( $product_id );
}