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@Zakelly @masteryhx The code has been adjusted, please help me take a look again.

@masteryhx Hi,this pr blocks another pr. Can you help me take a look? By the way, this change caused a python test error. Since I don’t have much experience in...

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@Zakelly @masteryhx What further discussions are needed on the modification of the python part? This PR has been on hold for some time.

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@Zakelly @masteryhx A new `ExternalizedCheckpointRetention.py` is created, the old one is marked as deprecated, and a separate commit for the python part is split.

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@Zakelly Flink-ci has passed