====== 16. ENV Variables ======
<code yaml pod_with_env.yaml>
apiVersion: v1
kind: Pod 
metadata:
  name: myapp-pod  #string
  labels:
    app: myapp
    anyKey: AnyValue
spec:
  containers: #List/Array
    - name: nginx-container
      image: nginx
      
      env:
        - name: env_name
          value: env_value
        - name: env_name_2
          valueFrom:
            configMapKeyRef:
        - name: env_name_3
          valueFrom:
            secretsKeyRef:
</code>