code: func validateGTLDs(entries []util.GTLDPeriod) error {
  	for _, gTLD := range entries {
  		// All entries should have a valid delegation date
  		if _, err := time.Parse(util.GTLDPeriodDateFormat, gTLD.DelegationDate); err != nil {
  			return err
  		}
  		// a gTLD that has not been removed has an empty RemovalDate and that's OK
  		if _, err := time.Parse(util.GTLDPeriodDateFormat, gTLD.RemovalDate); gTLD.RemovalDate != "" && err != nil {
  			return err
  		}
  	}
  	return nil
  }
docs: // validateGTLDs checks that all entries have a valid parseable DelegationDate
  // string, and if not-empty, a valid parseable RemovalDate string. This function
  // assumes an entry with an empty DelegationDate is an error. Use
  // `delegatedGTLDs` to filter out entries that were never delegated before
  // validating.