This example creates a Sankey diagram from car evaluation data, showing the proportional relationships between categorical attributes such as buying price, maintenance cost, doors, persons, luggage boot, and safety. Each node represents a specific attribute value, and links between nodes encode the conditional ratio of one value occurring given another across all possible column pairs. The code loads data from a remote CSV, parses it with `d3.csvParse`, and builds nodes and links programmatically before passing them to the `render` function. Although the Sankey layout is not executed, the visualization relies on the D3 v5 library and the external sankey.js plugin.