This visualization displays the Iris dataset as a scatter plot comparing sepal length against petal length, with each of the three flower species distinguished by a unique symbol shape. The plot includes labeled axes and a shape legend to identify species. The code uses D3 v7 APIs including `d3.scaleLinear`, `d3.scaleOrdinal`, `d3.symbol`, `d3.symbolsFill`, and `d3.axisLeft`/`d3.axisBottom`. Data is loaded asynchronously from a CSV file and parsed with `d3.csvParse`, with numeric columns explicitly coerced.