This example shows a simple pie chart visualizing the distribution of four categories (one, two, three, four) with values from an embedded CSV string. The chart renders as an SVG with colored arcs, each filled using a categorical color scale based on the category name. The code uses d3.svg.arc to define the pie slices and d3.layout.pie to compute the angles, with data parsed via d3.csv.parse. The visualization is centered on a 960×500 canvas with a white background and white stroke separators between arcs.