BUMP 4.20.0.dev

[sleepyStick]

PYTHON-XXXX

Changes in this PR

I think this is normally done during the release workflow but that step was broken (I've filed a ticket to fix it)

I believe this is the only thing it did? If there's something else that needs to be done, please let me know!

Test Plan

Checklist

Checklist for Author

• Did you update the changelog (if necessary)?
• Is there test coverage?
• Is any followup work tracked in a JIRA ticket? If so, add link(s).

Checklist for Reviewer

• Does the title of the PR reference a JIRA Ticket?
• Do you fully understand the implementation? (Would you be comfortable explaining how this code works to someone else?)
• Is all relevant documentation (README or docstring) updated?

[Copilot]

🟢 Approval recommended

The version-only change is compatible with existing version handling and has no identified blocking issues.

0 open findings

What changed in this PR

Starts PyMongo’s next development cycle by manually applying the version bump missed by the release workflow.

Changes:

• Updates __version__ from 4.19.0 to 4.20.0.dev.

File	Description
pymongo/​_version.py	Sets the next development version.

🧠 Review effort: Balanced

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[aclark4life]

Thanks! Should be dev0 though I think

[sleepyStick]

Thanks! Should be dev0 though I think

ah good catch, thanks