code: func IsFullyQualifiedName(fldPath *field.Path, name string) field.ErrorList {
  	var allErrors field.ErrorList
  	if len(name) == 0 {
  		return append(allErrors, field.Required(fldPath, ""))
  	}
  	if errs := IsDNS1123Subdomain(name); len(errs) > 0 {
  		return append(allErrors, field.Invalid(fldPath, name, strings.Join(errs, ",")))
  	}
  	if len(strings.Split(name, ".")) < 3 {
  		return append(allErrors, field.Invalid(fldPath, name, "should be a domain with at least three segments separated by dots"))
  	}
  	return allErrors
  }
docs: // IsFullyQualifiedName checks if the name is fully qualified.