This code is a Pine script for TradingView that plots a vertical line on the chart n bars away from the current candle on the current time frame. The number of bars and line color can be customized by the user using input fields. The script calculates the highest and lowest price on the chart for the past n bars, and then draws a vertical line at the target bar with the specified line color. The previous line is removed and the ID of the new line is stored so that the next time the script is run, it can be removed and replaced with a new line. This script can be useful for marking important points on a chart or for visually tracking patterns or trends over time.