This example demonstrates the initial steps of building a bar chart, showing population data for North African countries as it is loaded and processed from a CSV file. The visualization currently only sets up the SVG canvas dimensions via `select` and `attr`, while the core chart rendering is not yet implemented. The code imports `select` and `csv` from D3 v5, reads the `data.csv` file, converts the population values from strings to numbers, and multiplies them by 1,000 to reflect actual population counts. The bar chart itself has yet to be drawn, as only the data preparation phase is visible.