feat: drop python 3.10 support (#2469)

# What does this PR do?

dropped python3.10, updated pyproject and dependencies, and also removed
some blocks of code with special handling for enum.StrEnum

Closes #2458

Signed-off-by: Charlie Doern <cdoern@redhat.com>

llama_stack/providers/utils/bedrock/refreshable_boto_session.py

@@ -87,9 +87,7 @@ class RefreshableBotoSession:
                 "access_key": session_credentials.access_key,
                 "secret_key": session_credentials.secret_key,
                 "token": session_credentials.token,
-                "expiry_time": datetime.datetime.fromtimestamp(
-                    time() + self.session_ttl, datetime.timezone.utc
-                ).isoformat(),
+                "expiry_time": datetime.datetime.fromtimestamp(time() + self.session_ttl, datetime.UTC).isoformat(),
             }
 
         return credentials

llama_stack/providers/utils/inference/stream_utils.py

@@ -5,7 +5,7 @@
 # the root directory of this source tree.
 
 from collections.abc import AsyncIterator
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from typing import Any
 
 from llama_stack.apis.inference import (
@@ -122,7 +122,7 @@ async def stream_and_store_openai_completion(
             final_response = OpenAIChatCompletion(
                 id=id,
                 choices=assembled_choices,
-                created=created or int(datetime.now(timezone.utc).timestamp()),
+                created=created or int(datetime.now(UTC).timestamp()),
                 model=model,
                 object="chat.completion",
             )

llama_stack/providers/utils/scheduler.py

@@ -9,7 +9,7 @@ import asyncio
 import functools
 import threading
 from collections.abc import Callable, Coroutine, Iterable
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from enum import Enum
 from typing import Any, TypeAlias
 
@@ -61,7 +61,7 @@ class Job:
         self._handler = handler
         self._artifacts: list[JobArtifact] = []
         self._logs: list[LogMessage] = []
-        self._state_transitions: list[tuple[datetime, JobStatus]] = [(datetime.now(timezone.utc), JobStatus.new)]
+        self._state_transitions: list[tuple[datetime, JobStatus]] = [(datetime.now(UTC), JobStatus.new)]
 
     @property
     def handler(self) -> JobHandler:
@@ -77,7 +77,7 @@ class Job:
             raise ValueError(f"Job is already in a completed state ({self.status})")
         if self.status == status:
             return
-        self._state_transitions.append((datetime.now(timezone.utc), status))
+        self._state_transitions.append((datetime.now(UTC), status))
 
     @property
     def artifacts(self) -> list[JobArtifact]:
@@ -215,7 +215,7 @@ class Scheduler:
         self._backend = _get_backend_impl(backend)
 
     def _on_log_message_cb(self, job: Job, message: str) -> None:
-        msg = (datetime.now(timezone.utc), message)
+        msg = (datetime.now(UTC), message)
         # At least for the time being, until there's a better way to expose
         # logs to users, log messages on console
         logger.info(f"Job {job.id}: {message}")

llama_stack/providers/utils/telemetry/tracing.py

@@ -11,7 +11,7 @@ import queue
 import random
 import threading
 from collections.abc import Callable
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from functools import wraps
 from typing import Any
 
@@ -121,7 +121,7 @@ class TraceContext:
             span_id=generate_span_id(),
             trace_id=self.trace_id,
             name=name,
-            start_time=datetime.now(timezone.utc),
+            start_time=datetime.now(UTC),
             parent_span_id=current_span.span_id if current_span else None,
             attributes=attributes,
         )
@@ -239,7 +239,7 @@ class TelemetryHandler(logging.Handler):
             UnstructuredLogEvent(
                 trace_id=span.trace_id,
                 span_id=span.span_id,
-                timestamp=datetime.now(timezone.utc),
+                timestamp=datetime.now(UTC),
                 message=self.format(record),
                 severity=severity(record.levelname),
             )