WC: Custom Low Stock message

gistfile1.txt

/* Change the 'Only # left in stock' message on the WooCommerce product page to
 * simply show 'Low Stock'.
 * Add to your theme's functions.php file
 */
function custom_stock_totals($availability_html, $availability_text, $product) {
	if (substr($availability_text,0, 4)=="Only") {
		$availability_text = "Supplies are running low! Get your jam!";
	} 
	$availability_html = '<p class="stock ' . esc_attr( $availability['class'] ) . '">' . esc_html( $availability_text ) . '</p>';
	return 	$availability_html;
}
add_filter('woocommerce_stock_html', 'custom_stock_totals', 20, 3);

/** https://support.woothemes.com/hc/en-us/articles/203178095-How-to-display-Low-Stock-instead-of-Only-x-left-in-stock-on-product-page **/