code: func hasPerVersionField(crdSpec *apiextensions.CustomResourceDefinitionSpec) bool {
  	if crdSpec == nil {
  		return false
  	}
  	for _, v := range crdSpec.Versions {
  		if v.Schema != nil || v.Subresources != nil || len(v.AdditionalPrinterColumns) > 0 {
  			return true
  		}
  	}
  	return false
  }
docs: // hasPerVersionField returns true if a CRD uses per-version schema/subresources/columns fields.
  //func hasPerVersionField(versions []apiextensions.CustomResourceDefinitionVersion) bool {