Use TypeAlias where possible for type aliases (#7630)

stubs/protobuf/google/protobuf/internal/decoder.pyi

@@ -1,10 +1,11 @@
 from typing import Any, Callable
+from typing_extensions import TypeAlias
 
 from google.protobuf.descriptor import Descriptor, FieldDescriptor
 from google.protobuf.message import Message
 
-_Decoder = Callable[[str, int, int, Message, dict[FieldDescriptor, Any]], int]
-_NewDefault = Callable[[Message], Message]
+_Decoder: TypeAlias = Callable[[str, int, int, Message, dict[FieldDescriptor, Any]], int]
+_NewDefault: TypeAlias = Callable[[Message], Message]
 
 def ReadTag(buffer, pos): ...
 

stubs/protobuf/google/protobuf/internal/encoder.pyi

@@ -1,8 +1,9 @@
 from typing import Callable
+from typing_extensions import TypeAlias
 
 from google.protobuf.descriptor import FieldDescriptor
 
-_Sizer = Callable[[int, bool, bool], int]
+_Sizer: TypeAlias = Callable[[int, bool, bool], int]
 
 Int32Sizer: _Sizer
 UInt32Sizer: _Sizer
@@ -19,7 +20,7 @@ def MessageSetItemSizer(field_number: int) -> _Sizer: ...
 def MapSizer(field_descriptor: FieldDescriptor, is_message_map: bool) -> _Sizer: ...
 def TagBytes(field_number: int, wire_type: int) -> bytes: ...
 
-_Encoder = Callable[[Callable[[bytes], int], bytes, bool], int]
+_Encoder: TypeAlias = Callable[[Callable[[bytes], int], bytes, bool], int]
 
 Int32Encoder: _Encoder
 UInt32Encoder: _Encoder

stubs/protobuf/google/protobuf/text_format.pyi

@@ -1,5 +1,6 @@
 from _typeshed import SupportsWrite
 from typing import Any, Callable, Iterable, Text, TypeVar
+from typing_extensions import TypeAlias
 
 from .descriptor import FieldDescriptor
 from .descriptor_pool import DescriptorPool
@@ -20,7 +21,7 @@ class TextWriter:
     def getvalue(self) -> str: ...
     def close(self) -> None: ...
 
-_MessageFormatter = Callable[[Message, int, bool], Text | None]
+_MessageFormatter: TypeAlias = Callable[[Message, int, bool], Text | None]
 
 def MessageToString(
     message: Message,