code: func hasAddrsplosion(addrs []ma.Multiaddr) bool {
  	aset := make(map[string]int)
  
  	for _, a := range addrs {
  		key, port := addrKeyAndPort(a)
  		xport, ok := aset[key]
  		if ok && port != xport {
  			return true
  		}
  		aset[key] = port
  	}
  
  	return false
  }
docs: // we have addrsplosion if for some protocol we advertise multiple ports on
  // the same base address.