title: how to add a section to the WooCommerce settings "Shipping" tab
body: <p>The filter hook <code>woocommerce_sections_shipping</code> is not working to add a section tab to woocommerce shipping settings: </p>
  
  <pre><code> if ( ! class_exists('WC_Shipping_Calculator')){
      class WC_Shipping_Calculator{
          public function __construct(){
  
              add_filter('woocommerce_get_settings_shipping', array( $this, 'add_settings_tab'), 100);
              //add_filter('woocommerce_settings_tabs_array', array( $this, 'add_settings_tab'), 100);
              //add_filter('woocommerce_sections_shipping_array', array( $this, 'add_settings_tab'), 100);
          }
  
          public function add_settings_tab($settings_tabs){
              $settings_tabs['shipping_calculator'] = __('Shipping Calculator', 'shipping-calculator');
              return $settings_tabs;
  
          }
      }
  }
  
  $GLOBAL['wc_shipping_calculator'] = new WC_Shipping_Calculator();
  </code></pre>
  
  <p>What is the filter that I can use to add a section tab to woocommerce shipping settings?</p>