def last(self):
        """
        Returns another NdLayout constituted of the last views of the
        individual elements (if they are maps).
        """
        last_items = []
        for (k, v) in self.items():
            if isinstance(v, NdMapping):
                item = (k, v.clone((v.last_key, v.last)))
            elif isinstance(v, AdjointLayout):
                item = (k, v.last)
            else:
                item = (k, v)
            last_items.append(item)
        return self.clone(last_items)
Returns another NdLayout constituted of the last views of the
        individual elements (if they are maps).