code: func (p *Peer) VersionKnown() bool {
  	p.flagsMtx.Lock()
  	versionKnown := p.versionKnown
  	p.flagsMtx.Unlock()
  
  	return versionKnown
  }
docs: // VersionKnown returns the whether or not the version of a peer is known
  // locally.
  //
  // This function is safe for concurrent access.