This example displays the classic Iris dataset as a scatter plot, mapping sepal length to the x-axis and petal length to the y-axis with D3 v7 scales. Each species is distinguished by a unique symbol from `d3.symbolsFill`, such as circles or triangles, through an ordinal scale. The visualization includes labeled axes and a custom shape legend built with D3’s `symbol` generator. Data is loaded via `fetch` and parsed with `d3.csvParse`, then rendered inside an SVG using modular functions for axes, plotting, and the legend.