code: func ValidateEndpointsUpdate(newEndpoints, oldEndpoints *core.Endpoints) field.ErrorList {
  	allErrs := ValidateObjectMetaUpdate(&newEndpoints.ObjectMeta, &oldEndpoints.ObjectMeta, field.NewPath("metadata"))
  	allErrs = append(allErrs, validateEndpointSubsets(newEndpoints.Subsets, field.NewPath("subsets"))...)
  	allErrs = append(allErrs, ValidateEndpointsSpecificAnnotations(newEndpoints.Annotations, field.NewPath("annotations"))...)
  	return allErrs
  }
docs: // ValidateEndpointsUpdate tests to make sure an endpoints update can be applied.
  // NodeName changes are allowed during update to accommodate the case where nodeIP or PodCIDR is reused.
  // An existing endpoint ip will have a different nodeName if this happens.