def get_mask(self, subject, xfmname, maskname):
        try:
            group = self.h5['subjects'][subject]['transforms'][xfmname]['masks']
            return group[maskname]
        except (KeyError, __HOLE__):
            raise IOError('Mask not found in package')
dataset/ETHPy150Open gallantlab/pycortex/cortex/dataset/__init__.py/Dataset.get_mask