As per [Sample_Types](https://github.com/planetarypy/planetaryimage/blob/master/planetaryimage/pds3image.py#L74) mapping table, we might have 1 `dtype` for multiple `sample_types`. Make sure that, `dtype` mapping table has main `sample_type` which should not be an alias of other `sample_type`.
As per Sample_Types mapping table, we might have 1
dtypefor multiplesample_types.Make sure that,
dtypemapping table has mainsample_typewhich should not be an alias of othersample_type.