[jrmccluskey]

When upgrading the Dataflow Templates Beam version in GoogleCloudPlatform/DataflowTemplates#4430 a small timestamp bug was surfaced: PyArrow 25+ returns timestamp data with the zone specified as zoneinfo.ZoneInfo('UTC') rather than the pytz representation. This standard was introduced as part of PEP 615 and has existed in every Python release since 3.9. A small fix was introduced in the templates PR to unblock that version upgrade, this fixes the bug in the Beam repo properly.

[github-actions]

📋 Review Summary

This PR updates Timestamp.from_utc_datetime to accept datetime.datetime objects with zoneinfo.ZoneInfo("UTC") in addition to pytz.utc and datetime.timezone.utc, addressing PyArrow 19+ timestamp conversion compatibility.

🔍 General Feedback

• The logic and unit test addition directly address the zoneinfo.ZoneInfo("UTC") compatibility requirement.
• Consider checking the ZoneInfo instance and its .key attribute (or guarding against ZoneInfoNotFoundError) instead of instantiating zoneinfo.ZoneInfo("UTC") during validation, so environments without OS-level tzdata or the tzdata package (e.g., Windows without optional dependencies) do not raise ZoneInfoNotFoundError when validating non-UTC tzinfo objects.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.90%. Comparing base (76f6e6d) to head (51da4d5).
⚠️ Report is 193 commits behind head on master.

Additional details and impacted files

@@              Coverage Diff              @@
##             master   #40613       +/-   ##
=============================================
+ Coverage     56.16%   79.90%   +23.73%     
=============================================
  Files          1124      488      -636     
  Lines        178336    82428    -95908     
  Branches       1489        0     -1489     
=============================================
- Hits         100170    65861    -34309     
+ Misses        75645    16567    -59078     
+ Partials       2521        0     -2521     

Flag	Coverage Δ
go	?
java	?
python	79.90% <100.00%> (+0.34%)	⬆️

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[github-actions]

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