Whole yaml

apiVersion: v1
kind: Service
metadata:
  name: mongodb
spec:
  type: ClusterIP
  selector:
    name: mongodb
  ports:
    - port: 27017
      targetPort: 27017
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: slow
provisioner: kubernetes.io/gce-pd
parameters:
  type: pd-standard
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mongo-volume-claim
spec:
  storageClassName: "slow"
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 512Mi
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: mongodb
spec:
  serviceName: mongodb
  replicas: 1
  selector:
    matchLabels:
      name: mongodb
  template:
    metadata:
      labels:
        name: mongodb
    spec:
      containers:
      - name: mongodb
        image: mongo:6.0
        args: ['--dbpath','/data/db']
        env:
          - name: MONGO_INITDB_ROOT_USERNAME
            value: root
          - name: MONGO_INITDB_ROOT_PASSWORD
            value: root
        volumeMounts:
          - name: 'mongo-volume-claim'
            mountPath: '/data/db'
      volumes:
        - name: mongo-volume-claim
          persistentVolumeClaim:
            claimName: 'mongo-volume-claim'