This D3.js pie chart visualizes the top 10 car-producing countries for 2019, using a categorical color scale to distinguish each nation. The code loads CSV data from a Gist, aggregates the values, and renders the chart with SVG paths using `d3.pie` and `d3.arc`. A legend, built with `d3.scaleOrdinal` and custom text elements, displays country names and their production totals formatted in thousands.