code: def ensure_pod_is_valid_after_unpickling(pod: V1Pod) -> V1Pod | None:
      """
      Convert pod to json and back so that pod is safe.
  
      The pod_override in executor_config is a V1Pod object.
      Such objects created with one k8s version, when unpickled in
      an env with upgraded k8s version, may blow up when
      `to_dict` is called, because openapi client code gen calls
      getattr on all attrs in openapi_types for each object, and when
      new attrs are added to that list, getattr will fail.
  
      Here we re-serialize it to ensure it is not going to blow up.
  
      :meta private:
      """
      try:
          # if to_dict works, the pod is fine
          pod.to_dict()
          return pod
      except AttributeError:
          pass
      try:
          from kubernetes.client.models.v1_pod import V1Pod
      except ImportError:
          return None
      if not isinstance(pod, V1Pod):
          return None
      try:
          try:
              from airflow.providers.cncf.kubernetes.pod_generator import (
                  PodGenerator,
              )
          except ImportError:
              from airflow.kubernetes.pre_7_4_0_compatibility.pod_generator import (  # type: ignore[assignment]
                  PodGenerator,
              )
          # now we actually reserialize / deserialize the pod
          pod_dict = sanitize_for_serialization(pod)
          return PodGenerator.deserialize_model_dict(pod_dict)
      except Exception:
          return None
  
imports: from __future__ import annotations
  import contextlib
  import copy
  import datetime
  import json
  import logging
  from typing import TYPE_CHECKING, Any, Generator, Iterable, overload
  from dateutil import relativedelta
  from sqlalchemy import TIMESTAMP, PickleType, event, nullsfirst, tuple_
  from sqlalchemy.dialects import mysql
  from sqlalchemy.types import JSON, Text, TypeDecorator
  from airflow.configuration import conf
  from airflow.serialization.enums import Encoding
  from airflow.utils.timezone import make_naive, utc
label_desc: Use image node_id 2 for calling a global function with example usage: ensure_pod_is_valid_after_unpickling(pod) and returns: pod, None, PodGenerator, None, None