ts by start offset and
        annotation id. If by_ol is True, sorts by start offset, end offset and annotation id.

        Args:
            by_ol: if True, use start offset, end offset, annotation id
        &#34;&#34;&#34;
        if by_ol:
            # we sort by increasing start offset then increasing annotation id for this
            self._key_start = _KeyStartEndAnnid()
            self._by_start = SortedKeyList(key=self._key_start)
        else:
            # we sort by increasing start offset t