code: func checkIPNetCollision(hostonly *net.IPNet, hostIfaces map[string]*net.IPNet) (bool, error) {
  	for _, ifaceNet := range hostIfaces {
  		if hostonly.IP.Equal(ifaceNet.IP.Mask(ifaceNet.Mask)) {
  			return true, nil
  		}
  	}
  	return false, nil
  }
docs: // checkIPNetCollision returns true if any host interfaces conflict with the host-only network mask passed as a parameter.
  // This works with IPv4 or IPv6 ip addresses.