| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| k8s.io/apimachinery/pkg/api/validation | Package validation contains generic api type validation functions. |
| k8s.io/apimachinery/pkg/util/validation | |
| k8s.io/apimachinery/pkg/util/validation/field | |
| k8s.io/kubernetes/pkg/apis/apiserverinternal | Package apiserverinternal contains the "internal" version of the API used by the apiservers themselves. |
| k8s.io/kubernetes/pkg/apis/core/validation | Package validation has functions for validating the correctness of api objects and explaining what is wrong with them when they aren't valid. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |