A test print file exactly 220x220mm with a height of 0.2mm (one layer) to match the Creality Ender V3 KE's build plate, with squares at the points where the auto levelling sensor touches the bed. 

This has the bonus of allowing you to analyze whether or not the CR-Touch sensor measurements are accurate or if any need adjusted.

Simply print at 0.2mm layer height and check the printed squares for any inconsistencies that would indicate too high or low a measurement point.

May work for other printers with a 220x220mm build plate that use a 5x5 bed mesh.