Uncertainty on photometric zeropoint

I am trying to have access to the estimated uncertainty on the photometric zeropoint.

I could get the zeropoint value with :

mag_zp = calexp.getPhotoCalib().instFluxToMagnitude(1)

But I did not manage to access the uncertainty on this zeropoint.
Can somebody help ?
Thanks in advance,

If you do dir(calexp.getPhotoCalib()), you should see a method called getCalibrationErr.

You should also explore the other overrides of the instFluxToMagnitude method, which include errors.