def _get(self, key, source, none=None, empty=None): value = None keys = self.map(key) for key in keys: value = source.get(key) if value is not None: break if empty is not None and b9.empty(value): return empty elif none is not None and value is None: return none else: return value
def empty(self, key): return b9.empty(self.get(key))