Iterate over items in a sequence from a given offset.

        Args:
            offs (int): The offset to begin iterating from.

        Yields:
            (indx, valu): The index and valu of the item.

def iter(self, offs):
        '''
        Iterate over items in a sequence from a given offset.

        Args:
            offs (int): The offset to begin iterating from.

        Yields:
            (indx, valu): The index and valu of the item.
        '''
        startkey = s_common.int64en(offs)

        for lkey, lval in self.slab.scanByRange(startkey, db=self.db):
            indx = s_common.int64un(lkey)
            valu = s_msgpack.un(lval)
            yield indx, valu