Fix Version/s: None
When attempting to access decam data under the dataset type "deepDiff_differenceExp", the mapper throws an exception:
File "/software/lsstsw/stack/Linux64/obs_base/12.1-20-gb6b4be1+6/python/lsst/obs/base/cameraMapper.py", line 387, in stdClosure
return mapping.standardize(mapper, item, dataId)
File "/software/lsstsw/stack/Linux64/obs_base/12.1-20-gb6b4be1+6/python/lsst/obs/base/mapping.py", line 312, in standardize
return mapper._standardizeExposure(self, item, dataId)
File "/software/lsstsw/stack/Linux64/obs_base/12.1-20-gb6b4be1+6/python/lsst/obs/base/cameraMapper.py", line 952, in _standardizeExposure
if mapping.level.lower() == "amp":
AttributeError: 'ExposureMapping' object has no attribute 'level'
It is true that deepDiff_differenceExp does not have a level attribute specified. It is unclear to me where the level attribute should be initialized if it is not specified in the policy file. Simon Krughoff points at this line in obs_base as a candidate location for setting level to None if it is not otherwise specified. The decam policy file does contain a statement defaultLevel: "sensor", but that does not seem to be implemented.