This example shows the number of viewers in millions for various sports using a pie chart and an accompanying legend. The data is loaded from a CSV file via `d3.csv`, and each section’s value label and legend entry are formatted with `d3.format`. The pie layout is generated using `d3.pie`, with arcs drawn via `d3.arc` into an SVG canvas, while `d3.scaleOrdinal` maps categorical colors to the slices. React is used as the framework, though rendering is handled directly through D3’s DOM manipulation.