Purpose of the change

Fix bug in tools/chatgpt2memmachine/migration.py
convert string to timestamp

Description

Fix bug in tools/chatgpt2memmachine/migration.py
convert string to timestamp

No dependencies

Fixes/Closes

Fixes #497

Type of change

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• [ x] Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration.

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• [ x] Unit Test

Test Results: [Attach logs, screenshots, or relevant output]

[memmachine@ai1 MemMachine]$ uv run pytest tools/chatgpt2memmachine/
============================================== test session starts ===============================================
platform linux -- Python 3.12.12, pytest-8.4.2, pluggy-1.6.0
rootdir: /home/memmachine/MemMachine
configfile: pyproject.toml
plugins: asyncio-1.2.0, langsmith-0.4.37, anyio-4.11.0
asyncio: mode=Mode.STRICT, debug=False, asyncio_default_fixture_loop_scope=session, asyncio_default_test_loop_scope=session
collected 1 item

tools/chatgpt2memmachine/test_migration.py . [100%]

=============================================== 1 passed in 0.18s ================================================

Checklist

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• [ x] I have signed the commit(s) within this pull request
• [ x] My code follows the style guidelines of this project (See STYLE_GUIDE.md)
• [ x] I have performed a self-review of my own code
• [ x] My changes generate no new warnings
• [ x] New and existing unit tests pass locally with my changes

Maintainer Checklist

• Confirmed all checks passed
• Contributor has signed the commit(s)
• Reviewed the code
• Run, Tested, and Verified the change(s) work as expected

Screenshots/Gifs

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Further comments

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