Big diff: Use new "|" union syntax (#5872)

stdlib/hmac.pyi

@@ -1,7 +1,7 @@
 import sys
 from _typeshed import ReadableBuffer
 from types import ModuleType
-from typing import Any, AnyStr, Callable, Optional, Union, overload
+from typing import Any, AnyStr, Callable, Union, overload
 
 # TODO more precise type for object of hashlib
 _Hash = Any
@@ -13,18 +13,18 @@ if sys.version_info >= (3, 8):
     # In reality digestmod has a default value, but the function always throws an error
     # if the argument is not given, so we pretend it is a required argument.
     @overload
-    def new(key: bytes, msg: Optional[ReadableBuffer], digestmod: _DigestMod) -> HMAC: ...
+    def new(key: bytes, msg: ReadableBuffer | None, digestmod: _DigestMod) -> HMAC: ...
     @overload
     def new(key: bytes, *, digestmod: _DigestMod) -> HMAC: ...
 
 else:
-    def new(key: bytes, msg: Optional[ReadableBuffer] = ..., digestmod: Optional[_DigestMod] = ...) -> HMAC: ...
+    def new(key: bytes, msg: ReadableBuffer | None = ..., digestmod: _DigestMod | None = ...) -> HMAC: ...
 
 class HMAC:
     digest_size: int
     block_size: int
     name: str
-    def __init__(self, key: bytes, msg: Optional[ReadableBuffer] = ..., digestmod: _DigestMod = ...) -> None: ...
+    def __init__(self, key: bytes, msg: ReadableBuffer | None = ..., digestmod: _DigestMod = ...) -> None: ...
     def update(self, msg: ReadableBuffer) -> None: ...
     def digest(self) -> bytes: ...
     def hexdigest(self) -> str: ...