This example visualizes municipal data from a CSV file, mapping regions to rectangular blocks without encoding any numeric values into visual properties; it merely displays the data. The code uses D3 v5 to load and parse the data, then applies a band scale to potentially position the rectangles. However, it only appends fixed-size rectangles using SVG, relying on the `csv` and `scaleBand` APIs. The visualization does not yet implement meaningful geometry, color, or axes.