diff --git a/client/src/telethon/_impl/tl/core/reader.py b/client/src/telethon/_impl/tl/core/reader.py
index b5d7acd7..6cc51907 100644
--- a/client/src/telethon/_impl/tl/core/reader.py
+++ b/client/src/telethon/_impl/tl/core/reader.py
@@ -1,16 +1,16 @@
 import functools
 import struct
 from collections.abc import Callable
-from typing import TYPE_CHECKING, Any, Optional, Protocol, Type, runtime_checkable
+from typing import TYPE_CHECKING, Any, Optional, Type
 
 if TYPE_CHECKING:
-
-    @runtime_checkable
-    class Buffer(Protocol):
-        def __buffer__(self, flags: int, /) -> memoryview: ...
+    from typing import Protocol
 
     from .serializable import Serializable
 
+    class Buffer(Protocol):
+        def __buffer__(self, flags: int, /) -> memoryview: ...
+
 
 def _bootstrap_get_ty(constructor_id: int) -> Optional[Type["Serializable"]]:
     # Lazy import because generate code depends on the Reader.