Support district VN in backend

	// In general settings
  add_filter( 'woocommerce_general_settings', array( $this, 'add_VN_districts_in_general_settings' ) );

	public function add_VN_districts_in_general_settings( $settings ) {
		$settings[3] = array(
				'title'    => __( 'City', 'woocommerce' ),
				'desc'     => __( 'The city in which your business is located.', 'woocommerce' ),
				'id'       => 'woocommerce_store_city',
				'default'  => '',
				'type'     => 'select',
				'desc_tip' => true,
				'options'  => array(
					'HUNG-YEN' => 'Hung Yen',
					'HA-GIANG' => 'Ha Giang',	
          // Get option for provinces selected $key => $value
				),
			);

		return $settings;
	}