This pie chart visualizes the protein content (in grams) of various cereals, displaying each cereal as a colored slice with a corresponding legend. The chart uses D3 v5, reading CSV data from a GitHub gist, and renders the pie slices using the `pie` and `arc` functions. Each slice is filled based on the cereal name using a categorical color scale, while legends are appended with a rect and text, with protein values formatted using `format` and genre-specific styling.