Use TypeAlias where possible for type aliases (#7630)

stdlib/dbm/__init__.pyi

@@ -1,13 +1,13 @@
 from _typeshed import Self
 from types import TracebackType
 from typing import Iterator, MutableMapping
-from typing_extensions import Literal
+from typing_extensions import Literal, TypeAlias
 
 __all__ = ["open", "whichdb", "error"]
 
-_KeyType = str | bytes
-_ValueType = str | bytes
-_TFlags = Literal[
+_KeyType: TypeAlias = str | bytes
+_ValueType: TypeAlias = str | bytes
+_TFlags: TypeAlias = Literal[
     "r",
     "w",
     "c",

stdlib/dbm/dumb.pyi

@@ -1,11 +1,12 @@
 from _typeshed import Self
 from types import TracebackType
 from typing import Iterator, MutableMapping
+from typing_extensions import TypeAlias
 
 __all__ = ["error", "open"]
 
-_KeyType = str | bytes
-_ValueType = str | bytes
+_KeyType: TypeAlias = str | bytes
+_ValueType: TypeAlias = str | bytes
 
 error = OSError
 

stdlib/dbm/gnu.pyi

@@ -2,11 +2,12 @@ import sys
 from _typeshed import Self
 from types import TracebackType
 from typing import TypeVar, overload
+from typing_extensions import TypeAlias
 
 if sys.platform != "win32":
     _T = TypeVar("_T")
-    _KeyType = str | bytes
-    _ValueType = str | bytes
+    _KeyType: TypeAlias = str | bytes
+    _ValueType: TypeAlias = str | bytes
 
     open_flags: str
 

stdlib/dbm/ndbm.pyi

@@ -2,11 +2,12 @@ import sys
 from _typeshed import Self
 from types import TracebackType
 from typing import TypeVar, overload
+from typing_extensions import TypeAlias
 
 if sys.platform != "win32":
     _T = TypeVar("_T")
-    _KeyType = str | bytes
-    _ValueType = str | bytes
+    _KeyType: TypeAlias = str | bytes
+    _ValueType: TypeAlias = str | bytes
 
     class error(OSError): ...
     library: str