This line chart displays one week of temperature in degrees Celsius for San Francisco, sourced from Data Canvas - Sense Your City. It uses D3 v5 with SVG rendering to plot a smooth curve via `d3.line` with `curveBasis`, scaled through `scaleTime` and `scaleLinear`. The visualization includes axes with gridlines and labels for time and temperature. The code also fetches daily COVID-19 testing data from the COVID Tracking API, though the rendered chart focuses on the temperature series.