---
title: "Discussion on \"LangGraph 'Could not reconstruct builtins.set from checkpoint': why a set of tuples comes back as a list\" | Hashnode"
description: "Discussion on \"LangGraph 'Could not reconstruct builtins.set from checkpoint': why a set of tuples comes back as a list\". Disclosure: I work on MemorySync (I'm Mohammed, the founder). I drafted this article with AI assistance and checked it against the GitHub issue, the langgraph-checkpoint source, the published LangGrap"
url: "https://hashnode.com/posts/langgraph-could-not-reconstruct-builtins-set-from-checkpoint/6af09f6798fe0effe84c79dd"
---

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[MemorySync](https://hashnode.com/@memorysync)

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22h ago

# [LangGraph 'Could not reconstruct builtins.set from checkpoint': why a set of tuples comes back as a list](https://memorysync.hashnode.dev/langgraph-could-not-reconstruct-builtins-set-from-checkpoint?utm_source=hashnode&utm_medium=feed)

Disclosure: I work on MemorySync (I'm Mohammed, the founder). I drafted this article with AI assistance and checked it against the GitHub issue, the langgraph-checkpoint source, the published LangGrap

memorysync.hashnode.dev 13 min read

[#debugging](https://hashnode.com/tag/debugging) [#langchain](https://hashnode.com/tag/langchain) [#langgraph](https://hashnode.com/tag/langgraph) [#python](https://hashnode.com/tag/python) [#ai](https://hashnode.com/tag/ai)

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