This example shows the beginning of a bar chart using population data for ten countries, where each country is rendered as a square rectangle of fixed size rather than a proportionally scaled bar. The visualization is built with D3.js version 5, using `select`, `csv`, and `scaleLinear` from the D3 library, and renders directly to an SVG element. The code loads the data from `data.csv`, multiplies each population value by 1000, and appends `<rect>` elements to the SVG, though the chart remains incomplete as no scales or axes are yet applied.