public function is_available( $package ) {
		$is_available = 'yes' === $this->enabled;

		if ( $is_available && $this->get_valid_postcodes() ) {
			$is_available = $this->is_valid_postcode( $package['destination']['postcode'], $package['destination']['country'] );
		}

		if ( $is_available ) {
			if ( 'specific' === $this->availability ) {
				$ship_to_countries = $this->countries;
			} else {
				$ship_to_countries = array_keys( WC()->countries->get_shipping_countries() );
			}
			if ( is_array( $ship_to_countries ) && ! in_array( $package['destination']['country'], $ship_to_countries, true ) ) {
				$is_available = false;
			}
		}

		return apply_filters( 'woocommerce_shipping_' . $this->id . '_is_available', $is_available, $package, $this );
	}