code: func GetBootFileURL(o dhcp6.Options) (*URL, error) {
  	v, err := o.GetOne(dhcp6.OptionBootFileURL)
  	if err != nil {
  		return nil, err
  	}
  
  	u := new(URL)
  	err = u.UnmarshalBinary(v)
  	return u, err
  }
docs: // GetBootFileURL returns the Boot File URL Option value, described in RFC
  // 5970, Section 3.1.
  //
  // The URL return value contains a URL which may be used by clients to obtain
  // a boot file for PXE.