This scatterplot visualizes the Iris dataset, plotting sepal length against petal length and using different symbol shapes to distinguish the three iris species. The visualization is rendered with d3.v7, employing `scaleLinear` for the axes, `scaleOrdinal` with `symbolsFill` for shape encoding, and a custom `shapeLegend` to map each symbol to its species. The data is loaded asynchronously from a GitHub-hosted CSV file via the Fetch API and parsed with `csvParse`.