code: func (p *Peer) UpdateLastAnnouncedBlock(blkHash *chainhash.Hash) {
  	log.Tracef("Updating last blk for peer %v, %v", p.addr, blkHash)
  
  	p.statsMtx.Lock()
  	p.lastAnnouncedBlock = blkHash
  	p.statsMtx.Unlock()
  }
docs: // UpdateLastAnnouncedBlock updates meta-data about the last block hash this
  // peer is known to have announced.
  //
  // This function is safe for concurrent access.