public function init_form_fields() {
            /* translators: %s: list of placeholders */
            $placeholder_text  = sprintf( __( 'Available placeholders: %s', 'woocommerce' ), '<code>' . esc_html( implode( '</code>, <code>', array_keys( $this->placeholders ) ) ) . '</code>' );
            $this->form_fields = array(
                'enabled'            => array(