Add text about namespace walkthrough

Closes: #4270

docs/tasks/administer-cluster/namespaces-walkthrough.md

@@ -63,6 +63,10 @@ Create the development namespace using kubectl.
 $ kubectl create -f https://k8s.io/docs/tasks/administer-cluster/namespace-dev.json
 ```
 
+Save the following contents into file [`namespace-prod.json`](/docs/admin/namespaces/namespace-prod.json) which describes a production namespace:
+
+{% include code.html language="json" file="namespace-prod.json" ghlink="/docs/tasks/administer-cluster/namespace-prod.json" %}
+
 And then let's create the production namespace using kubectl.
 
 ```shell
@@ -123,12 +127,57 @@ lithe-cocoa-92103_kubernetes
 The next step is to define a context for the kubectl client to work in each namespace. The value of "cluster" and "user" fields are copied from the current context.
 
 ```shell
-$ kubectl config set-context dev --namespace=development --cluster=lithe-cocoa-92103_kubernetes --user=lithe-cocoa-92103_kubernetes
-$ kubectl config set-context prod --namespace=production --cluster=lithe-cocoa-92103_kubernetes --user=lithe-cocoa-92103_kubernetes
+$ kubectl config set-context dev --namespace=development \
+  --cluster=lithe-cocoa-92103_kubernetes \
+  --user=lithe-cocoa-92103_kubernetes
+$ kubectl config set-context prod --namespace=production \
+  --cluster=lithe-cocoa-92103_kubernetes \
+  --user=lithe-cocoa-92103_kubernetes
 ```
 
-The above commands provided two request contexts you can alternate against depending on what namespace you
-wish to work against.
+By default, the above commands adds two contexts that are saved into file
+`.kube/config`. You can now view the contexts and alternate against the two
+new request contexts depending on which namespace you wish to work against.
+
+To view the new contexts:
+
+```shell
+$ kubectl config view
+apiVersion: v1
+clusters:
+- cluster:
+    certificate-authority-data: REDACTED
+    server: https://130.211.122.180
+  name: lithe-cocoa-92103_kubernetes
+contexts:
+- context:
+    cluster: lithe-cocoa-92103_kubernetes
+    user: lithe-cocoa-92103_kubernetes
+  name: lithe-cocoa-92103_kubernetes
+- context:
+    cluster: lithe-cocoa-92103_kubernetes
+    namespace: development
+    user: lithe-cocoa-92103_kubernetes
+  name: dev
+- context:
+    cluster: lithe-cocoa-92103_kubernetes
+    namespace: production
+    user: lithe-cocoa-92103_kubernetes
+  name: prod
+current-context: lithe-cocoa-92103_kubernetes
+kind: Config
+preferences: {}
+users:
+- name: lithe-cocoa-92103_kubernetes
+  user:
+    client-certificate-data: REDACTED
+    client-key-data: REDACTED
+    token: 65rZW78y8HbwXXtSXuUw9DbP4FLjHi4b
+- name: lithe-cocoa-92103_kubernetes-basic-auth
+  user:
+    password: h5M0FtUUIflBSdI7
+    username: admin
+
 
 Let's switch to operate in the development namespace.