This example visualizes the Iris dataset as a scatter plot of sepal length against petal length, with the three species distinguished by different symbol shapes. A shape legend identifies each species, and the plot includes styled axes with labels. The visualization is built using D3 v7, employing `scaleLinear` for the x and y scales, `scaleOrdinal` with `symbolsFill` for the shapes, and the `csvParse` method to load data from a GitHub-hosted CSV file. The `axes` and `shapeLegend` modules handle the axis and legend rendering.