Big diff: use lower-case list and dict (#5888)

stdlib/email/policy.pyi

@@ -3,7 +3,7 @@ from email.contentmanager import ContentManager
 from email.errors import MessageDefect
 from email.header import Header
 from email.message import Message
-from typing import Any, Callable, List, Tuple
+from typing import Any, Callable, Tuple
 
 class Policy:
     max_line_length: int | None
@@ -17,7 +17,7 @@ class Policy:
     def register_defect(self, obj: Message, defect: MessageDefect) -> None: ...
     def header_max_count(self, name: str) -> int | None: ...
     @abstractmethod
-    def header_source_parse(self, sourcelines: List[str]) -> Tuple[str, str]: ...
+    def header_source_parse(self, sourcelines: list[str]) -> Tuple[str, str]: ...
     @abstractmethod
     def header_store_parse(self, name: str, value: str) -> Tuple[str, str]: ...
     @abstractmethod
@@ -28,7 +28,7 @@ class Policy:
     def fold_binary(self, name: str, value: str) -> bytes: ...
 
 class Compat32(Policy):
-    def header_source_parse(self, sourcelines: List[str]) -> Tuple[str, str]: ...
+    def header_source_parse(self, sourcelines: list[str]) -> Tuple[str, str]: ...
     def header_store_parse(self, name: str, value: str) -> Tuple[str, str]: ...
     def header_fetch_parse(self, name: str, value: str) -> str | Header: ...  # type: ignore
     def fold(self, name: str, value: str) -> str: ...
@@ -41,7 +41,7 @@ class EmailPolicy(Policy):
     refold_source: str
     header_factory: Callable[[str, str], str]
     content_manager: ContentManager
-    def header_source_parse(self, sourcelines: List[str]) -> Tuple[str, str]: ...
+    def header_source_parse(self, sourcelines: list[str]) -> Tuple[str, str]: ...
     def header_store_parse(self, name: str, value: str) -> Tuple[str, str]: ...
     def header_fetch_parse(self, name: str, value: str) -> str: ...
     def fold(self, name: str, value: str) -> str: ...