Activity 7
This example visualizes the distribution of movies rated above 8.5 by genre as a pie chart, with a custom legend using distinct D3 symbols (circles, squares, triangles, diamonds, and crosses) for each genre. It loads CSV data asynchronously via `d3.csv`, converts the relevant column to numbers, and renders the chart as SVG using `d3.pie` and `d3.arc`. The visualization uses a color scale with `d3.schemeCategory10` and includes axis labels and a title, though no axes are drawn.