code: func (me CompactIPv4NodeInfo) MarshalBinary() ([]byte, error) {
  	return marshalBinarySlice(slices.Map(func(ni NodeInfo) NodeInfo {
  		ni.Addr.IP = ni.Addr.IP.To4()
  		return ni
  	}, me).(CompactIPv4NodeInfo))
  }
docs: // func (me *CompactIPv4NodeInfo) Scrub() {
  // 	slices.FilterInPlace(me, func(ni *NodeInfo) bool {
  // 		ni.Addr.IP = ni.Addr.IP.To4()
  // 		return ni.Addr.IP != nil
  // 	})
  // }