title: How get woocommerce product price before and after save
body: <p>I want get and set log for woocommerce variation product price after product price change. (after click on update product)</p>
  <p>EX :
  Product 1 :
  Variation 1 : old price : 10.000 , new price : 20.000
  Variation 2 : old price : 30.000 , new price : 50.000</p>
  <p>i test wp_insert_post_data filter and save_post_product action
  but i can't get old price and two function return new price</p>
  <p>How i can get product old price before new price saved in database</p>
  <p>**die at the end of function for see result.</p>
  <pre><code>add_action('save_post_product', 'save_post_action', 10, 3);
  function save_post_action( $post_id, $post, $update ) {
      if (get_post_type($post_id) !== 'product') return;
      $product = wc_get_product($post_id);
      $current_products = $product-&gt;get_children();
      foreach ($current_products as $variation_id) {
          $variable_product = wc_get_product($variation_id);
          //$regular_price = $variable_product-&gt;get_regular_price();
          //$sale_price = $variable_product-&gt;get_sale_price();
          $price = $variable_product-&gt;get_price();
          var_dump($price);
      }
      die;
  }
  </code></pre>