This example displays a loading message that reports the size, row count, and column count of a CSV dataset loaded from a gist, using D3's `csv` function to fetch and parse the data. The visualization is built with React, using `useState` and `useEffect` hooks to manage asynchronous data loading, and renders the summary text as an HTML `<pre>` element. The underlying D3 and React libraries are included via CDN, and the output is displayed at full browser window size.