Apply ruff Python 3.11 fixes to dev tooling, scripts and test suites (#74156)

Output of ruff --fix with the py311 target for dev/, scripts/ and the
e2e, integration and kubernetes test suites, followed by ruff format
where the shorter names let calls fit on one line: timezone.utc becomes
datetime.UTC. No behaviour change.

Four modules are left out: dev/registry/extract_metadata.py,
dev/registry/extract_versions.py and the update_airflow_pyproject_toml
and upgrade_dependency_floors prek scripts still fall back to tomli on
Python 3.10, so their UTC fixes land together with the removal of that
fallback in the requires-python bump.

airflow-e2e-tests/tests/airflow_e2e_tests/basic_tests/test_basic_dag_operations.py

@@ -16,7 +16,7 @@
 # under the License.
 from __future__ import annotations
 
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 from airflow_e2e_tests.e2e_test_utils.clients import AirflowClient
 
@@ -28,7 +28,7 @@ class TestBasicDagFunctionality:
 
     def test_xcom_value(self):
         resp = self.airflow_client.trigger_dag(
-            "example_xcom_test", json={"logical_date": datetime.now(timezone.utc).isoformat()}
+            "example_xcom_test", json={"logical_date": datetime.now(UTC).isoformat()}
         )
         self.airflow_client.wait_for_dag_run(
             dag_id="example_xcom_test",

airflow-e2e-tests/tests/airflow_e2e_tests/e2e_test_utils/base_remote_log_search_test.py

@@ -17,7 +17,7 @@
 from __future__ import annotations
 
 import time
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 import pytest
 
@@ -62,7 +62,7 @@ class BaseRemoteLoggingSearchTest:
 
         resp = self.airflow_client.trigger_dag(
             self.dag_id,
-            json={"logical_date": datetime.now(timezone.utc).isoformat()},
+            json={"logical_date": datetime.now(UTC).isoformat()},
         )
         run_id = resp["dag_run_id"]
         state = self.airflow_client.wait_for_dag_run(
@@ -117,7 +117,7 @@ class BaseRemoteLoggingSearchTest:
         self.airflow_client.un_pause_dag(dag_id)
         resp = self.airflow_client.trigger_dag(
             dag_id,
-            json={"logical_date": datetime.now(timezone.utc).isoformat()},
+            json={"logical_date": datetime.now(UTC).isoformat()},
         )
         run_id = resp["dag_run_id"]
         state = self.airflow_client.wait_for_dag_run(dag_id=dag_id, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/e2e_test_utils/clients.py

@@ -17,7 +17,7 @@
 from __future__ import annotations
 
 import time
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from functools import cached_property
 
 import boto3
@@ -174,7 +174,7 @@ class AirflowClient:
         """Trigger a DAG and wait for it to complete."""
         self.un_pause_dag(dag_id)
 
-        resp = self.trigger_dag(dag_id, json=json or {"logical_date": datetime.now(timezone.utc).isoformat()})
+        resp = self.trigger_dag(dag_id, json=json or {"logical_date": datetime.now(UTC).isoformat()})
 
         # Wait for the DAG run to complete
         return self.wait_for_dag_run(

airflow-e2e-tests/tests/airflow_e2e_tests/go_sdk_tests/test_go_sdk_concurrent_xcom.py

@@ -24,7 +24,7 @@ Asserts the task succeeds and the concurrent pull beats the sequential one.
 from __future__ import annotations
 
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 import pytest
 
@@ -57,7 +57,7 @@ class _CompletedRun:
 def completed_run() -> _CompletedRun:
     """Trigger ``concurrent_xcom_dag`` once and wait for it to finish."""
     client = AirflowClient()
-    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=_DAG_ID, run_id=run_id, timeout=_GO_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=_DAG_ID, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/go_sdk_tests/test_go_sdk_dag.py

@@ -68,7 +68,7 @@ from __future__ import annotations
 import re
 import time
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 import pytest
 
@@ -126,7 +126,7 @@ def completed_run() -> _CompletedRun:
     in this module inspects the resulting states, XComs, and logs.
     """
     client = AirflowClient()
-    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=_DAG_ID, run_id=run_id, timeout=_GO_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=_DAG_ID, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/go_sdk_tests/test_go_sdk_task_state.py

@@ -23,7 +23,7 @@ proven to have reached the database.
 from __future__ import annotations
 
 from dataclasses import dataclass
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from http import HTTPStatus
 
 import pytest
@@ -54,7 +54,7 @@ class _CompletedRun:
 @pytest.fixture(scope="module")
 def completed_run() -> _CompletedRun:
     client = AirflowClient()
-    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=_DAG_ID, run_id=run_id, timeout=_GO_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=_DAG_ID, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/go_sdk_tests/test_go_sdk_taskflow_binding.py

@@ -28,7 +28,7 @@ from __future__ import annotations
 
 import time
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 import pytest
 
@@ -86,7 +86,7 @@ class _CompletedRun:
 def completed_run() -> _CompletedRun:
     """Trigger ``taskflow_binding_dag`` once and wait for it to finish."""
     client = AirflowClient()
-    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=_DAG_ID, run_id=run_id, timeout=_GO_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=_DAG_ID, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/go_sdk_tests/test_go_sdk_variable_write.py

@@ -24,7 +24,7 @@ written, so both paths go through the supervisor and the Task Execution API.
 from __future__ import annotations
 
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from http import HTTPStatus
 
 import pytest
@@ -52,7 +52,7 @@ class _CompletedRun:
 def completed_run() -> _CompletedRun:
     """Trigger ``variable_write_dag`` once and wait for it to finish."""
     client = AirflowClient()
-    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(_DAG_ID, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=_DAG_ID, run_id=run_id, timeout=_GO_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=_DAG_ID, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/java_sdk_tests/test_java_sdk_dag.py

@@ -69,7 +69,7 @@ from __future__ import annotations
 
 import time
 from dataclasses import dataclass, field
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from http import HTTPStatus
 from typing import TYPE_CHECKING
 
@@ -155,7 +155,7 @@ def _trigger_and_wait_for_dag(dag_id: str, timeout: int) -> _CompletedRun:
     client = AirflowClient()
     run_id = None
     try:
-        resp = client.trigger_dag(dag_id, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+        resp = client.trigger_dag(dag_id, json={"logical_date": datetime.now(UTC).isoformat()})
         run_id = resp["dag_run_id"]
         state = client.wait_for_dag_run(dag_id=dag_id, run_id=run_id, timeout=timeout)
         ti_resp = client.get_task_instances(dag_id=dag_id, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/openlineage_tests/harness.py

@@ -75,7 +75,7 @@ class OpenLineageE2ERunner:
 
     def __init__(self, client: AirflowClient):
         self.client = client
-        now = dt.datetime.now(tz=dt.timezone.utc)
+        now = dt.datetime.now(tz=dt.UTC)
         self.run_id = f"ci_triggered_{now.isoformat()}"
         self.retry_run_id = f"{self.run_id}_retry1"
         # dag_id -> whether its final state came from retry_run_id rather than run_id; populated by run().
@@ -110,7 +110,7 @@ class OpenLineageE2ERunner:
             console.print(f"[red]Failed to unpause Dag `{dag_id}`: {exc}")
 
     def trigger_dag_run(self, dag_id: str, run_id: str) -> bool:
-        now = dt.datetime.now(tz=dt.timezone.utc).isoformat()
+        now = dt.datetime.now(tz=dt.UTC).isoformat()
         payload = {"dag_run_id": run_id, "logical_date": now, "conf": {}}
         try:
             self.client._make_request(method="POST", endpoint=f"dags/{dag_id}/dagRuns", json=payload)

airflow-e2e-tests/tests/airflow_e2e_tests/remote_log_tests/test_remote_logging.py

@@ -17,7 +17,7 @@
 from __future__ import annotations
 
 import time
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 
 import pytest
 
@@ -37,7 +37,7 @@ class TestRemoteLogging:
         self.airflow_client.un_pause_dag(TestRemoteLogging.dag_id)
 
         resp = self.airflow_client.trigger_dag(
-            TestRemoteLogging.dag_id, json={"logical_date": datetime.now(timezone.utc).isoformat()}
+            TestRemoteLogging.dag_id, json={"logical_date": datetime.now(UTC).isoformat()}
         )
         state = self.airflow_client.wait_for_dag_run(
             dag_id=TestRemoteLogging.dag_id,

airflow-e2e-tests/tests/airflow_e2e_tests/ts_sdk_tests/test_ts_sdk_dag.py

@@ -37,7 +37,7 @@ from __future__ import annotations
 
 import time
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from http import HTTPStatus
 
 import pytest
@@ -89,7 +89,7 @@ class _CompletedRun:
 
 def _trigger_and_wait(dag_id: str) -> _CompletedRun:
     client = AirflowClient()
-    resp = client.trigger_dag(dag_id, json={"logical_date": datetime.now(timezone.utc).isoformat()})
+    resp = client.trigger_dag(dag_id, json={"logical_date": datetime.now(UTC).isoformat()})
     run_id = resp["dag_run_id"]
     state = client.wait_for_dag_run(dag_id=dag_id, run_id=run_id, timeout=_TS_TASK_TIMEOUT)
     ti_resp = client.get_task_instances(dag_id=dag_id, run_id=run_id)

airflow-e2e-tests/tests/airflow_e2e_tests/xcom_object_storage_tests/test_xcom_object_storage_backend.py

@@ -17,7 +17,7 @@
 from __future__ import annotations
 
 import time
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pprint import pprint
 from uuid import uuid4
 
@@ -41,7 +41,7 @@ class TestXComObjectStorageBackend:
             self.dag_id,
             json={
                 "dag_run_id": f"test_xcom_object_storage_backend_{uuid4()}",
-                "logical_date": datetime.now(timezone.utc).isoformat(),
+                "logical_date": datetime.now(UTC).isoformat(),
             },
         )
         dag_run_id = trigger_resp["dag_run_id"]

dev/breeze/src/airflow_breeze/utils/github.py

@@ -23,7 +23,7 @@ import sys
 import tempfile
 import zipfile
 from collections.abc import Mapping, Sequence
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 from typing import TYPE_CHECKING, Any, cast
 
@@ -159,7 +159,7 @@ def log_github_rate_limit_error(response: Response) -> None:
     remaining_int = int(remaining) if remaining and remaining.isdigit() else None
 
     if reset and reset.isdigit():
-        reset_dt = datetime.fromtimestamp(int(reset), tz=timezone.utc)
+        reset_dt = datetime.fromtimestamp(int(reset), tz=UTC)
         reset_time = reset_dt.strftime("%Y-%m-%d %H:%M:%S UTC")
     else:
         reset_time = "unknown"
@@ -342,7 +342,7 @@ def get_tag_date(tag: str) -> str | None:
     timestamp: int = (
         tag_object.committed_date if hasattr(tag_object, "committed_date") else tag_object.tagged_date
     )
-    return datetime.fromtimestamp(timestamp, tz=timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+    return datetime.fromtimestamp(timestamp, tz=UTC).strftime("%Y-%m-%dT%H:%M:%SZ")
 
 
 def download_artifact_from_run_id(run_id: str, output_file: Path, github_repository: str, github_token: str):

dev/breeze/src/airflow_breeze/utils/kubernetes_utils.py

@@ -26,7 +26,7 @@ import stat
 import sys
 import tarfile
 import tempfile
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from pathlib import Path
 from time import sleep
 from typing import Any, NamedTuple
@@ -414,7 +414,7 @@ def get_kubernetes_port_numbers(python: str, kubernetes_version: str) -> tuple[i
 def _attempt_to_connect(port_number: int, output: Output | None, wait_seconds: int = 0) -> bool:
     import requests
 
-    start_time = datetime.now(timezone.utc)
+    start_time = datetime.now(UTC)
     sleep_seconds = 5
     for attempt in itertools.count(1):
         get_console(output=output).print(f"[info]Connecting to localhost:{port_number}. Num try: {attempt}")
@@ -437,7 +437,7 @@ def _attempt_to_connect(port_number: int, output: Output | None, wait_seconds: i
                 f"[warning]Error when connecting to localhost:{port_number} "
                 f"{response.status_code}: {response.reason}"
             )
-        current_time = datetime.now(timezone.utc)
+        current_time = datetime.now(UTC)
         if current_time - start_time > timedelta(seconds=wait_seconds):
             if wait_seconds > 0:
                 get_console(output=output).print(f"[error]More than {wait_seconds} passed. Exiting.")

dev/breeze/src/airflow_breeze/utils/parallel.py

@@ -283,7 +283,7 @@ class ParallelMonitor(Thread):
         self.time_in_seconds = time_in_seconds
         self.debug_resources = debug_resources
         self.progress_matcher = progress_matcher
-        self.start_time = datetime.datetime.now(tz=datetime.timezone.utc)
+        self.start_time = datetime.datetime.now(tz=datetime.UTC)
 
     def print_single_progress(self, output: Output):
         if self.progress_matcher:
@@ -312,7 +312,7 @@ class ParallelMonitor(Thread):
     def print_summary(self):
         import psutil
 
-        time_passed = datetime.datetime.now(tz=datetime.timezone.utc) - self.start_time
+        time_passed = datetime.datetime.now(tz=datetime.UTC) - self.start_time
         get_console().rule()
         for output in self.outputs:
             self.print_single_progress(output)

dev/breeze/tests/test_set_milestone.py

@@ -18,7 +18,7 @@ from __future__ import annotations
 
 import json
 import re
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -202,21 +202,13 @@ class TestShouldSkipMilestoneTagging:
 
     def test_skip_when_backport_unlabeled_with_no_replacement(self):
         # Events show backport removal, no backport on PR now → skip (check 2).
-        events = [
-            _unlabel_event(
-                "backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc)
-            )
-        ]
+        events = [_unlabel_event("backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC))]
         assert _should_skip_milestone_tagging(["kind:bug"], events=events)
 
     def test_no_skip_when_backport_replaced(self):
         # Events show backport-to-v3-1 removal but v3-2 remains on the PR → no skip.
         # The caller's regular evaluation will pick up the new label.
-        events = [
-            _unlabel_event(
-                "backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc)
-            )
-        ]
+        events = [_unlabel_event("backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC))]
         assert not _should_skip_milestone_tagging(["backport-to-v3-2-test", "kind:bug"], events=events)
 
     def test_no_skip_when_no_removal_event(self):
@@ -224,20 +216,14 @@ class TestShouldSkipMilestoneTagging:
         assert not _should_skip_milestone_tagging(["backport-to-v3-1-test", "kind:bug"], events=[])
 
     def test_no_skip_when_unrelated_label_removed(self):
-        events = [
-            _unlabel_event("kind:documentation", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc))
-        ]
+        events = [_unlabel_event("kind:documentation", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC))]
         assert not _should_skip_milestone_tagging(["kind:bug"], events=events)
 
     def test_events_check_takes_precedence_over_static_labels(self):
         # Both check 2 (events) and check 3 (static label) would fire here;
         # the function returns True on the first one — events — and never logs
         # the static-label reason.
-        events = [
-            _unlabel_event(
-                "backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc)
-            )
-        ]
+        events = [_unlabel_event("backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC))]
         assert _should_skip_milestone_tagging(["area:CI"], events=events)
 
     def test_events_none_disables_events_check(self):
@@ -251,10 +237,8 @@ class TestGetRemovedBackportLabelsFromEvents:
 
     def test_returns_all_unlabel_events_for_backports(self):
         events = [
-            _unlabel_event(
-                "backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc)
-            ),
-            _unlabel_event("backport-to-v3-2-test", "bob", datetime(2026, 5, 23, 14, 0, tzinfo=timezone.utc)),
+            _unlabel_event("backport-to-v3-1-test", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC)),
+            _unlabel_event("backport-to-v3-2-test", "bob", datetime(2026, 5, 23, 14, 0, tzinfo=UTC)),
         ]
         assert _get_removed_backport_labels_from_events(events) == {
             "backport-to-v3-1-test",
@@ -262,9 +246,7 @@ class TestGetRemovedBackportLabelsFromEvents:
         }
 
     def test_ignores_unrelated_label_unlabel_events(self):
-        events = [
-            _unlabel_event("kind:documentation", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=timezone.utc))
-        ]
+        events = [_unlabel_event("kind:documentation", "alice", datetime(2026, 5, 23, 12, 0, tzinfo=UTC))]
         assert _get_removed_backport_labels_from_events(events) == set()
 
     def test_ignores_non_unlabeled_events(self):
@@ -733,7 +715,7 @@ However, **no open milestone was found** matching: {expected_search_criteria}
             _unlabel_event(
                 "backport-to-v3-2-test",
                 "shahar1",
-                datetime(2026, 5, 23, 20, 32, 17, tzinfo=timezone.utc),
+                datetime(2026, 5, 23, 20, 32, 17, tzinfo=UTC),
             ),
         ]
         mock_get_client.return_value = mock_gh
@@ -785,7 +767,7 @@ However, **no open milestone was found** matching: {expected_search_criteria}
             _unlabel_event(
                 "backport-to-v3-2-test",
                 "testuser",
-                datetime(2026, 5, 23, 20, 32, 17, tzinfo=timezone.utc),
+                datetime(2026, 5, 23, 20, 32, 17, tzinfo=UTC),
             ),
         ]
         mock_get_client.return_value = mock_gh
@@ -834,7 +816,7 @@ However, **no open milestone was found** matching: {expected_search_criteria}
             _unlabel_event(
                 "backport-to-v3-1-test",
                 "testuser",
-                datetime(2026, 5, 23, 20, 30, 0, tzinfo=timezone.utc),
+                datetime(2026, 5, 23, 20, 30, 0, tzinfo=UTC),
             ),
         ]
         mock_milestone = MagicMock()

dev/registry/extract_connections.py

@@ -39,7 +39,7 @@ import argparse
 import json
 import sys
 from collections import defaultdict
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 from typing import Any
 
@@ -204,7 +204,7 @@ def main():
 
     hooks, form_widgets, field_behaviours = HookMetaService._get_hooks_with_mocked_fab()
 
-    generated_at = datetime.now(timezone.utc).isoformat()
+    generated_at = datetime.now(UTC).isoformat()
 
     # Group connection types by provider
     provider_connections: dict[str, list[dict]] = defaultdict(list)

dev/registry/extract_parameters.py

@@ -50,7 +50,7 @@ import textwrap
 import typing
 from collections import defaultdict
 from dataclasses import dataclass
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 
 import yaml
@@ -1233,7 +1233,7 @@ def main():
     for p in providers_data.get("providers", []):
         provider_versions[p["id"]] = p["version"]
 
-    generated_at = datetime.now(timezone.utc).isoformat()
+    generated_at = datetime.now(UTC).isoformat()
     _main_discover(
         provider_versions,
         generated_at,

kubernetes-tests/tests/kubernetes_tests/test_base.py

@@ -22,7 +22,7 @@ import re
 import subprocess
 import tempfile
 import time
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 from subprocess import check_call, check_output
 from typing import Literal
@@ -100,7 +100,7 @@ class BaseK8STest:
         with open(output_file_path, "w") as output_file:
             print("=" * 80, file=output_file)
             print(f"Describe resources for namespace {namespace}", file=output_file)
-            print(f"Datetime: {datetime.now(tz=timezone.utc)}", file=output_file)
+            print(f"Datetime: {datetime.now(tz=UTC)}", file=output_file)
             print("=" * 80, file=output_file)
             print("Describing pods", file=output_file)
             print("-" * 80, file=output_file)
@@ -349,7 +349,7 @@ class BaseK8STest:
         post_string = f"http://{host}/dags/{dag_id}/dagRuns"
         print(f"Calling [start_dag]#2 {post_string}")
 
-        logical_date = datetime.now(timezone.utc).isoformat()
+        logical_date = datetime.now(UTC).isoformat()
         # Trigger a new dagrun
         result = self.session.post(post_string, json={"logical_date": logical_date})
         try:

scripts/ci/analyze_ci_job_durations.py

@@ -75,7 +75,7 @@ import json
 import os
 import subprocess
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 from typing import TypedDict
 
@@ -725,7 +725,7 @@ def main() -> None:
     runs = get_recent_runs(repo, workflow, branch, max_runs, only_successful, event)
     # A degraded Actions API can return an old page of runs, and without this check its
     # weeks-old durations were reported as "latest" and raised a false alert.
-    newest_age_days = compute_run_age_days(runs[0], datetime.now(timezone.utc)) if runs else None
+    newest_age_days = compute_run_age_days(runs[0], datetime.now(UTC)) if runs else None
     if newest_age_days is not None and newest_age_days > max_latest_run_age_days:
         print(
             f"::warning::The newest usable run (#{runs[0]['run_number']}) is "

scripts/ci/notify_uv_lock_conflicts.py

@@ -49,7 +49,7 @@ import re
 import sys
 import time
 from dataclasses import dataclass
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from typing import Any
 
 import httpx
@@ -428,7 +428,7 @@ def main() -> int:
 
     short_sha = sha[:7]
     commit_url = f"https://github.com/{owner}/{repo}/commit/{sha}"
-    stale_cut = datetime.now(tz=timezone.utc) - timedelta(days=STALE_DAYS)
+    stale_cut = datetime.now(tz=UTC) - timedelta(days=STALE_DAYS)
 
     with GitHubGraphQL(token) as client:
         source_pr = resolve_source_pr(client, owner, repo, sha, short_sha)

scripts/ci/prek/upgrade_important_versions.py

@@ -37,7 +37,7 @@ import os
 import re
 import subprocess
 import sys
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from enum import Enum
 from pathlib import Path
 
@@ -277,7 +277,7 @@ def _is_version_within_cooldown(releases: dict, version: str, cooldown_hours: fl
         return False
     upload_time = datetime.fromisoformat(files[0]["upload_time_iso_8601"].replace("Z", "+00:00"))
     effective_hours = COOLDOWN_DAYS * 24 if cooldown_hours is None else cooldown_hours
-    cutoff = datetime.now(timezone.utc) - timedelta(hours=effective_hours)
+    cutoff = datetime.now(UTC) - timedelta(hours=effective_hours)
     return upload_time > cutoff
 
 

scripts/ci/slack_notification_state.py

@@ -44,7 +44,7 @@ import json
 import os
 import subprocess
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 
 REMINDER_INTERVAL_HOURS = 24
@@ -140,7 +140,7 @@ def determine_action(current_failures: list[str], prev_state: dict | None) -> st
     """
     prev_failures = sorted(prev_state.get("failures", [])) if prev_state else []
     prev_notified = prev_state.get("last_notified") if prev_state else None
-    now = datetime.now(timezone.utc)
+    now = datetime.now(UTC)
 
     if current_failures:
         if not prev_failures:
@@ -164,7 +164,7 @@ def determine_action(current_failures: list[str], prev_state: dict | None) -> st
 
 def save_state(current_failures: list[str], action: str, prev_notified: str | None) -> None:
     """Save current state to file for upload as artifact."""
-    now = datetime.now(timezone.utc)
+    now = datetime.now(UTC)
     STATE_DIR.mkdir(parents=True, exist_ok=True)
 
     new_state = {

scripts/in_container/update_quarantined_test_status.py

@@ -20,7 +20,7 @@ from __future__ import annotations
 import os
 import re
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 from typing import NamedTuple
 from urllib.parse import urlsplit
@@ -244,7 +244,7 @@ if __name__ == "__main__":
     print()
     with Path(__file__).resolve().with_name("quarantine_issue_header.md").open() as f:
         header = jinja2.Template(f.read(), autoescape=True, undefined=StrictUndefined).render(
-            DATE_UTC_NOW=datetime.now(tz=timezone.utc).isoformat("T", timespec="seconds")
+            DATE_UTC_NOW=datetime.now(tz=UTC).isoformat("T", timespec="seconds")
         )
     quarantined_issue.edit(
         title=None, body=f"{header}\n\n{table}", state="open" if test_results else "closed"

scripts/tests/ci/prek/test_upgrade_dependency_floors.py

@@ -18,7 +18,7 @@ from __future__ import annotations
 
 import subprocess
 import textwrap
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from pathlib import Path
 from unittest import mock
 
@@ -202,7 +202,7 @@ def test_no_exclusion_for_plain_floor(tmp_path):
     assert get_exclusion_reason("boto3", [_site("boto3>=1.40; python_version < '3.14'")], config) is None
 
 
-NOW = datetime(2026, 9, 24, tzinfo=timezone.utc)
+NOW = datetime(2026, 9, 24, tzinfo=UTC)
 AGE = timedelta(days=180)
 
 

scripts/tests/ci/prek/test_upgrade_important_versions.py

@@ -19,6 +19,7 @@
 
 from __future__ import annotations
 
+from datetime import UTC
 from unittest import mock
 
 import pytest
@@ -199,12 +200,12 @@ def test_remove_override_entry_no_match_is_noop():
 
 def test_is_version_within_cooldown_uses_per_package_override():
     """A shorter per-package cooldown lets a release through that the global window would block."""
-    from datetime import datetime, timedelta, timezone
+    from datetime import datetime, timedelta
 
     from ci.prek.upgrade_important_versions import _is_version_within_cooldown
 
     # Published 2 days ago — inside the 4-day global window, outside a 6-hour window.
-    two_days_ago = (datetime.now(timezone.utc) - timedelta(days=2)).isoformat()
+    two_days_ago = (datetime.now(UTC) - timedelta(days=2)).isoformat()
     releases = {"1.0.1": [{"upload_time_iso_8601": two_days_ago.replace("+00:00", "Z")}]}
 
     # No override → global 4-day cooldown applies → version is "within cooldown".

scripts/tests/ci/test_notify_uv_lock_conflicts.py

@@ -19,7 +19,7 @@ from __future__ import annotations
 import importlib.util
 import sys
 import types
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 from pathlib import Path
 from typing import Any
 from unittest.mock import MagicMock
@@ -56,7 +56,7 @@ def mod():
 
 # A recent timestamp — well inside the stale window — used by fixture PRs.
 FRESH_ISO = "2099-01-01T12:00:00Z"
-STALE_CUT = datetime(1970, 1, 1, tzinfo=timezone.utc)
+STALE_CUT = datetime(1970, 1, 1, tzinfo=UTC)
 SHORT_SHA = "abc1234"
 
 
@@ -113,11 +113,11 @@ class TestPrNumberRegex:
 class TestParseUpdatedAt:
     def test_handles_zulu_suffix(self, mod):
         dt = mod.parse_updated_at("2025-04-24T10:20:30Z")
-        assert dt == datetime(2025, 4, 24, 10, 20, 30, tzinfo=timezone.utc)
+        assert dt == datetime(2025, 4, 24, 10, 20, 30, tzinfo=UTC)
 
     def test_handles_explicit_offset(self, mod):
         dt = mod.parse_updated_at("2025-04-24T10:20:30+00:00")
-        assert dt == datetime(2025, 4, 24, 10, 20, 30, tzinfo=timezone.utc)
+        assert dt == datetime(2025, 4, 24, 10, 20, 30, tzinfo=UTC)
 
 
 class TestClassify:
@@ -126,7 +126,7 @@ class TestClassify:
         assert kind == "drafts" and entry is None
 
     def test_stale(self, mod):
-        cutoff = datetime.now(tz=timezone.utc) - timedelta(days=14)
+        cutoff = datetime.now(tz=UTC) - timedelta(days=14)
         old_pr = make_pr(updated_at="2000-01-01T00:00:00Z")
         kind, entry = mod.classify(old_pr, cutoff, SHORT_SHA)
         assert kind == "stale" and entry is None
@@ -237,9 +237,9 @@ class TestScanOpenPrs:
     def test_early_exit_on_stale(self, mod):
         """A stale PR stops pagination even if hasNextPage is True."""
         client = MagicMock()
-        recent_cut = datetime.now(tz=timezone.utc) - timedelta(days=1)
-        fresh = (datetime.now(tz=timezone.utc)).isoformat().replace("+00:00", "Z")
-        stale = (datetime.now(tz=timezone.utc) - timedelta(days=30)).isoformat().replace("+00:00", "Z")
+        recent_cut = datetime.now(tz=UTC) - timedelta(days=1)
+        fresh = (datetime.now(tz=UTC)).isoformat().replace("+00:00", "Z")
+        stale = (datetime.now(tz=UTC) - timedelta(days=30)).isoformat().replace("+00:00", "Z")
         client.call.return_value = self._page(
             [
                 make_pr(number=1, updated_at=fresh, mergeable="CONFLICTING"),

scripts/tests/ci/testing/test_compute_remaining_test_timeout.py

@@ -18,7 +18,7 @@ from __future__ import annotations
 
 import importlib.util
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 
 import pytest
@@ -61,7 +61,7 @@ def test_compute_remaining_test_timeout(
 
 @time_machine.travel("2026-08-29 12:10:00+00:00", tick=False)
 def test_main_derives_the_budget_left_from_the_job_start_time(timeout_module, monkeypatch, capsys):
-    job_start_epoch = int(datetime(2026, 8, 29, 12, 0, tzinfo=timezone.utc).timestamp())
+    job_start_epoch = int(datetime(2026, 8, 29, 12, 0, tzinfo=UTC).timestamp())
     monkeypatch.setattr(
         sys,
         "argv",

task-sdk-integration-tests/tests/task_sdk_tests/jwt_plugin.py

@@ -21,7 +21,7 @@ from __future__ import annotations
 
 import os
 import uuid
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from typing import Any
 
 import jwt
@@ -57,7 +57,7 @@ class JWTTokenGenerator:
         Returns:
             JWT token as a string
         """
-        now = int(datetime.now(timezone.utc).timestamp())
+        now = int(datetime.now(UTC).timestamp())
 
         claims = {
             "jti": uuid.uuid4().hex,

task-sdk-integration-tests/tests/task_sdk_tests/test_dag_run_operations.py

@@ -26,7 +26,7 @@ These tests validate the Execution API endpoints for DAG Run operations:
 
 from __future__ import annotations
 
-from datetime import datetime, timedelta, timezone
+from datetime import UTC, datetime, timedelta
 
 import pytest
 
@@ -145,7 +145,7 @@ def test_dag_run_get_previous(sdk_client, dag_info):
 
     response = sdk_client.dag_runs.get_previous(
         dag_id=dag_info["dag_id"],
-        logical_date=datetime.now(timezone.utc) + timedelta(seconds=10),
+        logical_date=datetime.now(UTC) + timedelta(seconds=10),
     )
 
     console.print(" Previous DAG Run Response ".center(72, "="))
@@ -169,7 +169,7 @@ def test_dag_run_get_previous_not_found(sdk_client):
 
     response = sdk_client.dag_runs.get_previous(
         dag_id="not_exist",
-        logical_date=datetime.now(timezone.utc) + timedelta(seconds=10),
+        logical_date=datetime.now(UTC) + timedelta(seconds=10),
     )
 
     console.print(" Non-existent Previous DAG Run Response ".center(72, "="))