This pie chart displays the distribution of students by municipality, based on a CSV dataset of exam results. It uses a d3 pie and arc to create a donut chart, with each slice labeled by municipal name and count. Data is loaded from a remote CSV file using d3.csv, and grouped with d3.rollup to count entries per municipality. The visualization is rendered as an SVG, colored with d3.scaleOrdinal and d3.schemeCategory10.