public function get_checkout_url( $post_id = null ) {
		if ( empty( $post_id ) ) {
			// There is currently no non-post specific checkout.
			return '';
		}

		$checkout_url = $this->get_cart_url( $post_id );

		/**
		 * Allow filtering of the PayPal Checkout URL.
		 *
		 * @since 4.11.0
		 *
		 * @param string $checkout_url PayPal Checkout URL.
		 */
		return apply_filters( 'tribe_tickets_tribe-commerce_checkout_url', $checkout_url );
	}