Deprecate ssl methods for NPN (#13823)

stdlib/ssl.pyi

@@ -28,7 +28,7 @@ from _ssl import (
 from _typeshed import ReadableBuffer, StrOrBytesPath, WriteableBuffer
 from collections.abc import Callable, Iterable
 from typing import Any, Literal, NamedTuple, TypedDict, overload, type_check_only
-from typing_extensions import Never, Self, TypeAlias
+from typing_extensions import Never, Self, TypeAlias, deprecated
 
 if sys.version_info >= (3, 13):
     from _ssl import HAS_PSK as HAS_PSK
@@ -369,7 +369,12 @@ class SSLSocket(socket.socket):
     def compression(self) -> str | None: ...
     def get_channel_binding(self, cb_type: str = "tls-unique") -> bytes | None: ...
     def selected_alpn_protocol(self) -> str | None: ...
-    def selected_npn_protocol(self) -> str | None: ...
+    if sys.version_info >= (3, 10):
+        @deprecated("Deprecated in 3.10. Use ALPN instead.")
+        def selected_npn_protocol(self) -> str | None: ...
+    else:
+        def selected_npn_protocol(self) -> str | None: ...
+
     def accept(self) -> tuple[SSLSocket, socket._RetAddress]: ...
     def unwrap(self) -> socket.socket: ...
     def version(self) -> str | None: ...
@@ -434,7 +439,12 @@ class SSLContext(_SSLContext):
     def set_default_verify_paths(self) -> None: ...
     def set_ciphers(self, cipherlist: str, /) -> None: ...
     def set_alpn_protocols(self, alpn_protocols: Iterable[str]) -> None: ...
-    def set_npn_protocols(self, npn_protocols: Iterable[str]) -> None: ...
+    if sys.version_info >= (3, 10):
+        @deprecated("Deprecated in 3.10. Use ALPN instead.")
+        def set_npn_protocols(self, npn_protocols: Iterable[str]) -> None: ...
+    else:
+        def set_npn_protocols(self, npn_protocols: Iterable[str]) -> None: ...
+
     def set_servername_callback(self, server_name_callback: _SrvnmeCbType | None) -> None: ...
     def load_dh_params(self, path: str, /) -> None: ...
     def set_ecdh_curve(self, name: str, /) -> None: ...
@@ -475,7 +485,12 @@ class SSLObject:
     @overload
     def getpeercert(self, binary_form: bool) -> _PeerCertRetType: ...
     def selected_alpn_protocol(self) -> str | None: ...
-    def selected_npn_protocol(self) -> str | None: ...
+    if sys.version_info >= (3, 10):
+        @deprecated("Deprecated in 3.10. Use ALPN instead.")
+        def selected_npn_protocol(self) -> str | None: ...
+    else:
+        def selected_npn_protocol(self) -> str | None: ...
+
     def cipher(self) -> tuple[str, str, int] | None: ...
     def shared_ciphers(self) -> list[tuple[str, str, int]] | None: ...
     def compression(self) -> str | None: ...