Command
:SENSe<Ch>:CORRection1:COLLect:SAVE
This command calculates the user calibration data after open/short/load measurements.
SENS:CORR2:COLL:SAVE causes an undefined header error.
Ana.WriteString ":SENS1:CORR1:COLL:SAVE", True
Cal > User Cal > Execute Cal > Done
SCPI.SENSE(Ch).CORRECTION(1).COLLECT.SAVE