code: func (pc *peerContainer) bundle(ip string) (*peerBundle, []*peerEvent) {
  	var events []*peerEvent
  	if _, ok := pc.Bundles[ip]; !ok {
  		location := pc.geodb.location(ip)
  		events = append(events, &peerEvent{
  			IP:       ip,
  			Location: location,
  		})
  		pc.Bundles[ip] = &peerBundle{
  			Location:   location,
  			KnownPeers: make(map[string]*knownPeer),
  		}
  	}
  	return pc.Bundles[ip], events
  }
docs: // bundle inserts a new peer bundle into the map, if the peer belonging
  // to the given IP wasn't metered so far. In this case retrieves the location of
  // the IP address from the database and creates a corresponding peer event.
  // Returns the bundle belonging to the given IP and the events occurring during
  // the initialization.