Kubernetes API call equivalent to ‘kubectl apply’

I checked the code in pkg/kubectl/cmd/apply.go and I think the following lines of code shows what’s behind the scene when you run kubectl apply -f:

// Compute a three way strategic merge patch to send to server.
patch, err := strategicpatch.CreateThreeWayMergePatch(original, modified, current, 
    versionedObject, true)
helper := resource.NewHelper(info.Client, info.Mapping)
_, err = helper.Patch(info.Namespace, info.Name, api.StrategicMergePatchType, patch)

And here is the code helper.Patch:

func (m *Helper) Patch(namespace, name string, pt api.PatchType, data []byte) (runtime.Object, error) {
    return m.RESTClient.Patch(pt).
        NamespaceIfScoped(namespace, m.NamespaceScoped).
        Resource(m.Resource).
        Name(name).
        Body(data).
        Do().
        Get()
}