This pie chart displays the distribution of city temperatures across three categories: low (<20°C), medium (20-30°C), and high (>30°C). The code loads CSV data from a remote GitHub gist using `d3.csvParse`, then uses `d3.pie()` and `d3.arc()` to generate SVG paths. A `d3.scaleOrdinal` with `d3.schemeCategory10` assigns colors to segments, while labels and a legend are added via D3 selections. The visualization is rendered entirely in SVG with D3 v7.