code: func GetIPs(code dhcp4.OptionCode, o dhcp4.Options) IPs {
  	v := o.Get(code)
  	if v == nil {
  		return nil
  	}
  
  	var i IPs
  	if err := i.UnmarshalBinary(v); err != nil {
  		return nil
  	}
  	return i
  }
docs: // GetIPs returns the list of IPs encoded in `code` option of `o`.