Loads a memory object from memory.

        :param page_idx: the index into the page
        :returns: a tuple of the object

def load_mo(self, state, page_idx):
        """
        Loads a memory object from memory.

        :param page_idx: the index into the page
        :returns: a tuple of the object
        """

        try:
            key = next(self._storage.irange(maximum=page_idx, reverse=True))
        except StopIteration:
            return None
        else:
            return self._storage[key]