Try to advance "Advanced.Peer.Ack.Point" according to RFC 3758.

def _update_advanced_peer_ack_point(self):
        """
        Try to advance "Advanced.Peer.Ack.Point" according to RFC 3758.
        """
        if uint32_gt(self._last_sacked_tsn, self._advanced_peer_ack_tsn):
            self._advanced_peer_ack_tsn = self._last_sacked_tsn

        done = 0
        streams = {}
        while self._sent_queue and self._sent_queue[0]._abandoned:
            chunk = self._sent_queue.popleft()
            self._advanced_peer_ack_tsn = chunk.tsn
            done += 1
            if not (chunk.flags & SCTP_DATA_UNORDERED):
                streams[chunk.stream_id] = chunk.stream_seq

        if done:
            # build FORWARD TSN
            self._forward_tsn_chunk = ForwardTsnChunk()
            self._forward_tsn_chunk.cumulative_tsn = self._advanced_peer_ack_tsn
            self._forward_tsn_chunk.streams = list(streams.items())