This line chart visualizes daily temperature measurements in San Francisco, with temperature on the y-axis and date on the x-axis, using a smooth curved path to connect the data points. The chart is rendered as an SVG using D3 v5, with scales created via `scaleTime` and `scaleLinear`, axes generated by `axisBottom` and `axisLeft`, and the line drawn using the `line` generator with `curveBasis` smoothing. The code loads temperature data from a CSV file, parses the date and numeric values, and displays gridlines with tick marks, axis labels, and a title.