<form method="POST">
    <h3>Editing: DataCountries.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * REST API Data countries controller.
 *
 * Handles requests to the /data/countries endpoint.
 */

namespace Automattic\WooCommerce\Admin\API;

defined( 'ABSPATH' ) || exit;

/**
 * REST API Data countries controller class.
 *
 * @internal
 * @extends WC_REST_Data_Countries_Controller
 */
class DataCountries extends \WC_REST_Data_Countries_Controller {

	/**
	 * Endpoint namespace.
	 *
	 * @var string
	 */
	protected $namespace = 'wc-analytics';

	/**
	 * Register routes.
	 *
	 * @since 3.5.0
	 */
	public function register_routes() {
		register_rest_route(
			$this-&gt;namespace,
			'/' . $this-&gt;rest_base . '/locales',
			array(
				array(
					'methods'             =&gt; \WP_REST_Server::READABLE,
					'callback'            =&gt; array( $this, 'get_locales' ),
					'permission_callback' =&gt; array( $this, 'get_items_permissions_check' ),
				),
				'schema' =&gt; array( $this, 'get_public_item_schema' ),
			)
		);

		parent::register_routes();
	}

	/**
	 * Get country fields.
	 *
	 * @return array
	 */
	public function get_locales() {
		$locales = WC()-&gt;countries-&gt;get_country_locale();
		return rest_ensure_response( $locales );
	}
}
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