Referencing a function from Commerce Coupon Module that no longer exists

Fatal error: Call to undefined function commerce_coupon_machine_name_code() in /sites/all/modules/commerce_coupon_pct/commerce_coupon_pct.module on line 193

The problem is commerce_coupon_machine_name_code from:

function commerce_coupon_pct_commerce_coupon_price_component_name_alter(&$price_component_name, $coupon) {
  if ($coupon->type == 'commerce_coupon_pct') {
    $price_component_name = $coupon->type . '_' . commerce_coupon_machine_name_code($coupon);
  }
}