chore: enable pyupgrade fixes (#1806)

# What does this PR do?

The goal of this PR is code base modernization.

Schema reflection code needed a minor adjustment to handle UnionTypes
and collections.abc.AsyncIterator. (Both are preferred for latest Python
releases.)

Note to reviewers: almost all changes here are automatically generated
by pyupgrade. Some additional unused imports were cleaned up. The only
change worth of note can be found under `docs/openapi_generator` and
`llama_stack/strong_typing/schema.py` where reflection code was updated
to deal with "newer" types.

Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>

llama_stack/templates/dev/dev.py

@@ -4,7 +4,6 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from typing import List, Tuple
 
 from llama_stack.apis.models.models import ModelType
 from llama_stack.distribution.datatypes import (
@@ -50,7 +49,7 @@ from llama_stack.templates.template import (
 )
 
 
-def get_inference_providers() -> Tuple[List[Provider], List[ModelInput]]:
+def get_inference_providers() -> tuple[list[Provider], list[ModelInput]]:
     # in this template, we allow each API key to be optional
     providers = [
         (

llama_stack/templates/llama_api/llama_api.py

@@ -4,7 +4,6 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from typing import List, Tuple
 
 from llama_stack.apis.models.models import ModelType
 from llama_stack.distribution.datatypes import (
@@ -36,7 +35,7 @@ from llama_stack.templates.template import (
 )
 
 
-def get_inference_providers() -> Tuple[List[Provider], List[ModelInput]]:
+def get_inference_providers() -> tuple[list[Provider], list[ModelInput]]:
     # in this template, we allow each API key to be optional
     providers = [
         (

llama_stack/templates/open-benchmark/open_benchmark.py

@@ -4,7 +4,6 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from typing import Dict, List, Tuple
 
 from llama_stack.apis.datasets import DatasetPurpose, URIDataSource
 from llama_stack.apis.models.models import ModelType
@@ -36,7 +35,7 @@ from llama_stack.templates.template import (
 )
 
 
-def get_inference_providers() -> Tuple[List[Provider], Dict[str, List[ProviderModelEntry]]]:
+def get_inference_providers() -> tuple[list[Provider], dict[str, list[ProviderModelEntry]]]:
     # in this template, we allow each API key to be optional
     providers = [
         (

llama_stack/templates/template.py

@@ -5,7 +5,7 @@
 # the root directory of this source tree.
 
 from pathlib import Path
-from typing import Dict, List, Literal, Optional, Tuple
+from typing import Literal
 
 import jinja2
 import yaml
@@ -32,8 +32,8 @@ from llama_stack.providers.utils.kvstore.config import SqliteKVStoreConfig
 
 
 def get_model_registry(
-    available_models: Dict[str, List[ProviderModelEntry]],
-) -> List[ModelInput]:
+    available_models: dict[str, list[ProviderModelEntry]],
+) -> list[ModelInput]:
     models = []
     for provider_id, entries in available_models.items():
         for entry in entries:
@@ -57,18 +57,18 @@ class DefaultModel(BaseModel):
 
 
 class RunConfigSettings(BaseModel):
-    provider_overrides: Dict[str, List[Provider]] = Field(default_factory=dict)
-    default_models: Optional[List[ModelInput]] = None
-    default_shields: Optional[List[ShieldInput]] = None
-    default_tool_groups: Optional[List[ToolGroupInput]] = None
-    default_datasets: Optional[List[DatasetInput]] = None
-    default_benchmarks: Optional[List[BenchmarkInput]] = None
+    provider_overrides: dict[str, list[Provider]] = Field(default_factory=dict)
+    default_models: list[ModelInput] | None = None
+    default_shields: list[ShieldInput] | None = None
+    default_tool_groups: list[ToolGroupInput] | None = None
+    default_datasets: list[DatasetInput] | None = None
+    default_benchmarks: list[BenchmarkInput] | None = None
 
     def run_config(
         self,
         name: str,
-        providers: Dict[str, List[str]],
-        container_image: Optional[str] = None,
+        providers: dict[str, list[str]],
+        container_image: str | None = None,
     ) -> StackRunConfig:
         provider_registry = get_provider_registry()
 
@@ -135,15 +135,15 @@ class DistributionTemplate(BaseModel):
     description: str
     distro_type: Literal["self_hosted", "remote_hosted", "ondevice"]
 
-    providers: Dict[str, List[str]]
-    run_configs: Dict[str, RunConfigSettings]
-    template_path: Optional[Path] = None
+    providers: dict[str, list[str]]
+    run_configs: dict[str, RunConfigSettings]
+    template_path: Path | None = None
 
     # Optional configuration
-    run_config_env_vars: Optional[Dict[str, Tuple[str, str]]] = None
-    container_image: Optional[str] = None
+    run_config_env_vars: dict[str, tuple[str, str]] | None = None
+    container_image: str | None = None
 
-    available_models_by_provider: Optional[Dict[str, List[ProviderModelEntry]]] = None
+    available_models_by_provider: dict[str, list[ProviderModelEntry]] | None = None
 
     def build_config(self) -> BuildConfig:
         return BuildConfig(

llama_stack/templates/verification/verification.py

@@ -4,7 +4,6 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from typing import Dict, List, Tuple
 
 from llama_stack.apis.models.models import ModelType
 from llama_stack.distribution.datatypes import (
@@ -51,7 +50,7 @@ from llama_stack.templates.template import (
 )
 
 
-def get_inference_providers() -> Tuple[List[Provider], Dict[str, List[ProviderModelEntry]]]:
+def get_inference_providers() -> tuple[list[Provider], dict[str, list[ProviderModelEntry]]]:
     # in this template, we allow each API key to be optional
     providers = [
         (