This example visualizes the classic Iris dataset, displaying sepal length on the x-axis and petal length on the y-axis as colored circles. The scatter plot uses `d3.scaleLinear` for axes and `d3.scaleOrdinal` with `schemeCategory10` to color-code the three species, with a custom color legend. It relies on `d3.csvParse` to load data from a CSV file, `d3-selection` and `selection.join` for DOM updates, and `axisLeft`/`axisBottom` for the axes, which are rendered with `d3.scaleLinear` domains computed via `extent`.