diff --git a/stdlib/pickle.pyi b/stdlib/pickle.pyi
index d063ccca7..0037091eb 100644
--- a/stdlib/pickle.pyi
+++ b/stdlib/pickle.pyi
@@ -169,3 +169,6 @@ FRAME: bytes
 
 def encode_long(x: int) -> bytes: ...  # undocumented
 def decode_long(data: bytes) -> int: ...  # undocumented
+
+_Pickler = Pickler  # undocumented
+_Unpickler = Unpickler  # undocumented