code: func (ar *AutoRelay) tryRelay(ctx context.Context, pi pstore.PeerInfo) bool {
  	if ar.usingRelay(pi.ID) {
  		return false
  	}
  
  	if !ar.connect(ctx, pi) {
  		return false
  	}
  
  	ar.mx.Lock()
  	defer ar.mx.Unlock()
  
  	// make sure we're still connected.
  	if ar.host.Network().Connectedness(pi.ID) != inet.Connected {
  		return false
  	}
  	ar.relays[pi.ID] = struct{}{}
  
  	return true
  }
docs: // addRelay adds the given relay to our set of relays.
  // returns true when we add a new relay