def value(self, view, template=None):
        out = AttrDict()
        for key, typ in self.subtemplates.items():
            out[key] = typ.value(view[key], self)
        return out
Get a dict with the same keys as the template and values
dataset/ETHPy150Open beetbox/beets/beets/util/confit.py/MappingTemplate.value